Vulnerabilities > CVE-2016-9942 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Libvncserver Project Libvncserver 0.9.10

047910
CVSS 9.8 - CRITICAL
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
network
low complexity
libvncserver-project
CWE-119
critical
nessus
NVD
Published: 2016-12-31
Updated: 2020-10-23

Summary

Heap-based buffer overflow in ultra.c in LibVNCClient in LibVNCServer before 0.9.11 allows remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions.

Vulnerable Configurations

Part Description Count
Application
Libvncserver_Project
1

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Client-side Injection-induced Buffer Overflow
    This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
  • Filter Failure through Buffer Overflow
    In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
  • MIME Conversion
    An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.

Nessus

  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-3171-1.NASL
    descriptionJosef Gajdusek discovered that the LibVNCServer client library incorrectly handled certain FrameBufferUpdate messages. If a user were tricked into connecting to a malicious server, an attacker could use this issue to cause a denial of service, or possibly execute arbitrary code. (CVE-2016-9941, CVE-2016-9942). Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    modified2020-06-02
    plugin id96445
    published2017-01-12
    reporterUbuntu Security Notice (C) 2017-2019 Canonical, Inc. / NASL script (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/96445
    titleUbuntu 12.04 LTS / 14.04 LTS / 16.04 LTS / 16.10 : libvncserver vulnerabilities (USN-3171-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3171-1. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include("compat.inc");

if (description)
{
  script_id(96445);
  script_version("3.6");
  script_cvs_date("Date: 2019/09/18 12:31:46");

  script_cve_id("CVE-2016-9941", "CVE-2016-9942");
  script_xref(name:"USN", value:"3171-1");

  script_name(english:"Ubuntu 12.04 LTS / 14.04 LTS / 16.04 LTS / 16.10 : libvncserver vulnerabilities (USN-3171-1)");
  script_summary(english:"Checks dpkg output for updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Ubuntu host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Josef Gajdusek discovered that the LibVNCServer client library
incorrectly handled certain FrameBufferUpdate messages. If a user were
tricked into connecting to a malicious server, an attacker could use
this issue to cause a denial of service, or possibly execute arbitrary
code. (CVE-2016-9941, CVE-2016-9942).

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://usn.ubuntu.com/3171-1/"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"Update the affected libvncclient1, libvncserver0 and / or
libvncserver1 packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libvncclient1");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libvncserver0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libvncserver1");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:12.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.10");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/12/31");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/01/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/01/12");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2017-2019 Canonical, Inc. / NASL script (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Ubuntu Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("ubuntu.inc");
include("misc_func.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! preg(pattern:"^(12\.04|14\.04|16\.04|16\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 12.04 / 14.04 / 16.04 / 16.10", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Ubuntu", cpu);

flag = 0;

if (ubuntu_check(osver:"12.04", pkgname:"libvncserver0", pkgver:"0.9.8.2-2ubuntu1.2")) flag++;
if (ubuntu_check(osver:"14.04", pkgname:"libvncserver0", pkgver:"0.9.9+dfsg-1ubuntu1.2")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"libvncclient1", pkgver:"0.9.10+dfsg-3ubuntu0.16.04.1")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"libvncserver1", pkgver:"0.9.10+dfsg-3ubuntu0.16.04.1")) flag++;
if (ubuntu_check(osver:"16.10", pkgname:"libvncclient1", pkgver:"0.9.10+dfsg-3ubuntu0.16.10.1")) flag++;
if (ubuntu_check(osver:"16.10", pkgname:"libvncserver1", pkgver:"0.9.10+dfsg-3ubuntu0.16.10.1")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libvncclient1 / libvncserver0 / libvncserver1");
}
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2017-DD5D2381E4.NASL
    descriptionUpdate to latest stable release, include fixes for gnutls and gtk-vnc compatibility. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-05
    modified2017-05-26
    plugin id100440
    published2017-05-26
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/100440
    titleFedora 24 : libvncserver (2017-dd5d2381e4)
    code
    #%NASL_MIN_LEVEL 80502
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2017-dd5d2381e4.
#

include("compat.inc");

if (description)
{
  script_id(100440);
  script_version("3.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2016-9941", "CVE-2016-9942");
  script_xref(name:"FEDORA", value:"2017-dd5d2381e4");

  script_name(english:"Fedora 24 : libvncserver (2017-dd5d2381e4)");
  script_summary(english:"Checks rpm output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Fedora host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Update to latest stable release, include fixes for gnutls and gtk-vnc
compatibility.

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as
possible without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bodhi.fedoraproject.org/updates/FEDORA-2017-dd5d2381e4"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected libvncserver package."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:libvncserver");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:24");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/12/31");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/05/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/05/26");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Fedora Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora");
os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! preg(pattern:"^24([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 24", "Fedora " + os_ver);

if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu);


flag = 0;
if (rpm_check(release:"FC24", reference:"libvncserver-0.9.11-2.fc24.1")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libvncserver");
}
  • NASL familySuSE Local Security Checks
    NASL idSUSE_SU-2018-0830-1.NASL
    descriptionLibVNCServer was updated to fix two security issues. These security issues were fixed : - CVE-2018-7225: Missing input sanitization inside rfbserver.c rfbProcessClientNormalMessage() (bsc#1081493). - CVE-2016-9942: Heap-based buffer overflow in ultra.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions (bsc#1017712). - CVE-2016-9941: Heap-based buffer overflow in rfbproto.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area (bsc#1017711). Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    modified2020-06-02
    plugin id108685
    published2018-03-28
    reporterThis script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/108685
    titleSUSE SLES12 Security Update : LibVNCServer (SUSE-SU-2018:0830-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from SUSE update advisory SUSE-SU-2018:0830-1.
# The text itself is copyright (C) SUSE.
#

include("compat.inc");

if (description)
{
  script_id(108685);
  script_version("1.5");
  script_cvs_date("Date: 2019/09/10 13:51:47");

  script_cve_id("CVE-2016-9941", "CVE-2016-9942", "CVE-2018-7225");

  script_name(english:"SUSE SLES12 Security Update : LibVNCServer (SUSE-SU-2018:0830-1)");
  script_summary(english:"Checks rpm output for the updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote SUSE host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"LibVNCServer was updated to fix two security issues. These security
issues were fixed :

  - CVE-2018-7225: Missing input sanitization inside
    rfbserver.c rfbProcessClientNormalMessage()
    (bsc#1081493).

  - CVE-2016-9942: Heap-based buffer overflow in ultra.c
    allowed remote servers to cause a denial of service
    (application crash) or possibly execute arbitrary code
    via a crafted FramebufferUpdate message with the Ultra
    type tile, such that the LZO payload decompressed length
    exceeds what is specified by the tile dimensions
    (bsc#1017712).

  - CVE-2016-9941: Heap-based buffer overflow in rfbproto.c
    allowed remote servers to cause a denial of service
    (application crash) or possibly execute arbitrary code
    via a crafted FramebufferUpdate message containing a
    subrectangle outside of the client drawing area
    (bsc#1017711).

Note that Tenable Network Security has extracted the preceding
description block directly from the SUSE security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.suse.com/show_bug.cgi?id=1017711"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.suse.com/show_bug.cgi?id=1017712"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.suse.com/show_bug.cgi?id=1081493"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.suse.com/security/cve/CVE-2016-9941/"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.suse.com/security/cve/CVE-2016-9942/"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.suse.com/security/cve/CVE-2018-7225/"
  );
  # https://www.suse.com/support/update/announcement/2018/suse-su-20180830-1/
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?3b21b199"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"To install this SUSE Security Update use the SUSE recommended
installation methods like YaST online_update or 'zypper patch'.

Alternatively you can run the command listed for your product :

SUSE Linux Enterprise Software Development Kit 12-SP3:zypper in -t
patch SUSE-SLE-SDK-12-SP3-2018-554=1

SUSE Linux Enterprise Software Development Kit 12-SP2:zypper in -t
patch SUSE-SLE-SDK-12-SP2-2018-554=1

SUSE Linux Enterprise Server for Raspberry Pi 12-SP2:zypper in -t
patch SUSE-SLE-RPI-12-SP2-2018-554=1

SUSE Linux Enterprise Server 12-SP3:zypper in -t patch
SUSE-SLE-SERVER-12-SP3-2018-554=1

SUSE Linux Enterprise Server 12-SP2:zypper in -t patch
SUSE-SLE-SERVER-12-SP2-2018-554=1"
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:LibVNCServer-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libvncclient0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libvncclient0-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libvncserver0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libvncserver0-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:suse_linux:12");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/12/31");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/03/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/03/28");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"SuSE Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/cpu", "Host/SuSE/release", "Host/SuSE/rpm-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/SuSE/release");
if (isnull(release) || release !~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "SUSE");
os_ver = pregmatch(pattern: "^(SLE(S|D)\d+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "SUSE");
os_ver = os_ver[1];
if (! preg(pattern:"^(SLES12)$", string:os_ver)) audit(AUDIT_OS_NOT, "SUSE SLES12", "SUSE " + os_ver);

if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if (cpu !~ "^i[3-6]86$" && "x86_64" >!< cpu && "s390x" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "SUSE " + os_ver, cpu);

sp = get_kb_item("Host/SuSE/patchlevel");
if (isnull(sp)) sp = "0";
if (os_ver == "SLES12" && (! preg(pattern:"^(2|3)$", string:sp))) audit(AUDIT_OS_NOT, "SLES12 SP2/3", os_ver + " SP" + sp);


flag = 0;
if (rpm_check(release:"SLES12", sp:"3", reference:"LibVNCServer-debugsource-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libvncclient0-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libvncclient0-debuginfo-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libvncserver0-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libvncserver0-debuginfo-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"LibVNCServer-debugsource-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libvncclient0-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libvncclient0-debuginfo-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libvncserver0-0.9.9-17.5.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libvncserver0-debuginfo-0.9.9-17.5.1")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:rpm_report_get());
  else security_hole(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "LibVNCServer");
}
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2017-0E08170FD3.NASL
    descriptionUpdate to latest stable release, include fixes for gnutls and gtk-vnc compatibility. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-05
    modified2017-05-26
    plugin id100434
    published2017-05-26
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/100434
    titleFedora 25 : libvncserver (2017-0e08170fd3)
    code
    #%NASL_MIN_LEVEL 80502
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2017-0e08170fd3.
#

include("compat.inc");

if (description)
{
  script_id(100434);
  script_version("3.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2016-9941", "CVE-2016-9942");
  script_xref(name:"FEDORA", value:"2017-0e08170fd3");

  script_name(english:"Fedora 25 : libvncserver (2017-0e08170fd3)");
  script_summary(english:"Checks rpm output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Fedora host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Update to latest stable release, include fixes for gnutls and gtk-vnc
compatibility.

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as
possible without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bodhi.fedoraproject.org/updates/FEDORA-2017-0e08170fd3"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected libvncserver package."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:libvncserver");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:25");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/12/31");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/05/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/05/26");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Fedora Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora");
os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! preg(pattern:"^25([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 25", "Fedora " + os_ver);

if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu);


flag = 0;
if (rpm_check(release:"FC25", reference:"libvncserver-0.9.11-2.fc25.1")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libvncserver");
}
  • NASL familySuSE Local Security Checks
    NASL idSUSE_SU-2017-0104-1.NASL
    descriptionLibVNCServer was updated to fix two security issues. These security issues were fixed : - CVE-2016-9941: Heap-based buffer overflow in rfbproto.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area (bsc#1017711) - CVE-2016-9942: Heap-based buffer overflow in ultra.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions (bsc#1017712) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    modified2020-06-02
    plugin id96429
    published2017-01-12
    reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/96429
    titleSUSE SLES11 Security Update : LibVNCServer (SUSE-SU-2017:0104-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from SUSE update advisory SUSE-SU-2017:0104-1.
# The text itself is copyright (C) SUSE.
#

include("compat.inc");

if (description)
{
  script_id(96429);
  script_version("3.6");
  script_cvs_date("Date: 2019/09/11 11:22:14");

  script_cve_id("CVE-2016-9941", "CVE-2016-9942");

  script_name(english:"SUSE SLES11 Security Update : LibVNCServer (SUSE-SU-2017:0104-1)");
  script_summary(english:"Checks rpm output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote SUSE host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"LibVNCServer was updated to fix two security issues. These security
issues were fixed :

  - CVE-2016-9941: Heap-based buffer overflow in rfbproto.c
    allowed remote servers to cause a denial of service
    (application crash) or possibly execute arbitrary code
    via a crafted FramebufferUpdate message containing a
    subrectangle outside of the client drawing area
    (bsc#1017711)

  - CVE-2016-9942: Heap-based buffer overflow in ultra.c
    allowed remote servers to cause a denial of service
    (application crash) or possibly execute arbitrary code
    via a crafted FramebufferUpdate message with the Ultra
    type tile, such that the LZO payload decompressed length
    exceeds what is specified by the tile dimensions
    (bsc#1017712)

Note that Tenable Network Security has extracted the preceding
description block directly from the SUSE security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.suse.com/show_bug.cgi?id=1017711"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.suse.com/show_bug.cgi?id=1017712"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.suse.com/security/cve/CVE-2016-9941/"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.suse.com/security/cve/CVE-2016-9942/"
  );
  # https://www.suse.com/support/update/announcement/2017/suse-su-20170104-1/
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?21fdedae"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"To install this SUSE Security Update use YaST online_update.
Alternatively you can run the command listed for your product :

SUSE Linux Enterprise Software Development Kit 11-SP4:zypper in -t
patch sdksp4-LibVNCServer-12932=1

SUSE Linux Enterprise Server 11-SP4:zypper in -t patch
slessp4-LibVNCServer-12932=1

SUSE Linux Enterprise Debuginfo 11-SP4:zypper in -t patch
dbgsp4-LibVNCServer-12932=1

To bring your system up-to-date, use 'zypper patch'."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:LibVNCServer");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:suse_linux:11");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/12/31");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/01/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/01/12");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"SuSE Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/cpu", "Host/SuSE/release", "Host/SuSE/rpm-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/SuSE/release");
if (isnull(release) || release !~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "SUSE");
os_ver = pregmatch(pattern: "^(SLE(S|D)\d+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "SUSE");
os_ver = os_ver[1];
if (! preg(pattern:"^(SLES11)$", string:os_ver)) audit(AUDIT_OS_NOT, "SUSE SLES11", "SUSE " + os_ver);

if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if (cpu !~ "^i[3-6]86$" && "x86_64" >!< cpu && "s390x" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "SUSE " + os_ver, cpu);

sp = get_kb_item("Host/SuSE/patchlevel");
if (isnull(sp)) sp = "0";
if (os_ver == "SLES11" && (! preg(pattern:"^(4)$", string:sp))) audit(AUDIT_OS_NOT, "SLES11 SP4", os_ver + " SP" + sp);


flag = 0;
if (rpm_check(release:"SLES11", sp:"4", reference:"LibVNCServer-0.9.1-159.1")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:rpm_report_get());
  else security_hole(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "LibVNCServer");
}
  • NASL familyGentoo Local Security Checks
    NASL idGENTOO_GLSA-201702-24.NASL
    descriptionThe remote host is affected by the vulnerability described in GLSA-201702-24 (LibVNCServer/LibVNCClient: Multiple vulnerabilities) Multiple vulnerabilities have been discovered in LibVNCServer and LibVNCClient. Please review the CVE identifiers referenced below for details. Impact : A remote attacker could entice a user to connect to a malicious VNC server or leverage Man-in-the-Middle attacks to cause the execution of arbitrary code with the privileges of the user running a VNC client linked against LibVNCClient. Workaround : There is no known workaround at this time.
    last seen2020-06-01
    modified2020-06-02
    plugin id97267
    published2017-02-21
    reporterThis script is Copyright (C) 2017 Tenable Network Security, Inc.
    sourcehttps://www.tenable.com/plugins/nessus/97267
    titleGLSA-201702-24 : LibVNCServer/LibVNCClient: Multiple vulnerabilities
  • NASL familySuSE Local Security Checks
    NASL idSUSE_SU-2017-0519-1.NASL
    descriptionThis update for tigervnc provides the following fixes : - Prevent malicious server from crashing a server via a buffer overflow, a similar flaw as the LibVNCServer issues CVE-2016-9941 and CVE-2016-9942.. (bsc#1019274) - CVE-2016-10207: Prevent potential crash due to insufficient clean-up after failure to establish TLS connection. (bsc#1023012) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    modified2020-06-02
    plugin id97299
    published2017-02-21
    reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/97299
    titleSUSE SLED12 / SLES12 Security Update : tigervnc (SUSE-SU-2017:0519-1)
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2017-6125002D79.NASL
    descriptionUpdate to latest stable release, include fixes for gnutls and gtk-vnc compatibility. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-05
    modified2017-07-17
    plugin id101644
    published2017-07-17
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/101644
    titleFedora 26 : libvncserver (2017-6125002d79)
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DSA-3753.NASL
    descriptionIt was discovered that libvncserver, a collection of libraries used to implement VNC/RFB clients and servers, incorrectly processed incoming network packets. This resulted in several heap-based buffer overflows, allowing a rogue server to either cause a DoS by crashing the client, or potentially execute arbitrary code on the client side.
    last seen2020-06-01
    modified2020-06-02
    plugin id96318
    published2017-01-06
    reporterThis script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/96318
    titleDebian DSA-3753-1 : libvncserver - security update
  • NASL familyHuawei Local Security Checks
    NASL idEULEROS_SA-2017-1046.NASL
    descriptionAccording to the versions of the libvncserver package installed, the EulerOS installation on the remote host is affected by the following vulnerabilities : - Heap-based buffer overflow in ultra.c in LibVNCClient in LibVNCServer before 0.9.11 allows remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions.(CVE-2016-9942,CVE-2016-9941) Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-05-06
    modified2017-05-01
    plugin id99891
    published2017-05-01
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/99891
    titleEulerOS 2.0 SP1 : libvncserver (EulerOS-SA-2017-1046)
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DLA-777.NASL
    descriptionIt was discovered that there were two vulnerabilities in libvncserver, a library to create/embed a VNC server : - CVE-2016-9941: Fix a heap-based buffer overflow that allows remote servers to cause a denial of service via a crafted FramebufferUpdate message containing a subrectangle outside of the drawing area. - CVE-2016-9942: Fix a heap-based buffer overflow that allow remote servers to cause a denial of service via a crafted FramebufferUpdate message with the
    last seen2020-03-17
    modified2017-01-04
    plugin id96272
    published2017-01-04
    reporterThis script is Copyright (C) 2017-2020 Tenable Network Security, Inc.
    sourcehttps://www.tenable.com/plugins/nessus/96272
    titleDebian DLA-777-1 : libvncserver security update
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DLA-1979.NASL
    descriptionSeveral vulnerabilities have been identified in the VNC code of iTALC, a classroom management software. All vulnerabilities referenced below are issues that have originally been reported against Debian source package libvncserver. The italc source package in Debian ships a custom-patched version of libvncserver, thus libvncserver
    last seen2020-06-01
    modified2020-06-02
    plugin id130408
    published2019-10-31
    reporterThis script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/130408
    titleDebian DLA-1979-1 : italc security update
  • NASL familySuSE Local Security Checks
    NASL idSUSE_SU-2017-0622-1.NASL
    descriptionThis update for tigervnc provides the following fixes : - Prevent malicious server from crashing a server via a buffer overflow, a similar flaw as the LibVNCServer issues CVE-2016-9941 and CVE-2016-9942. (bsc#1019274) - CVE-2016-10207: Prevent potential crash due to insufficient clean-up after failure to establish TLS connection. (bsc#1023012) Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    modified2020-06-02
    plugin id97598
    published2017-03-08
    reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/97598
    titleSUSE SLED12 / SLES12 Security Update : tigervnc (SUSE-SU-2017:0622-1)
  • NASL familySuSE Local Security Checks
    NASL idOPENSUSE-2018-326.NASL
    descriptionLibVNCServer was updated to fix two security issues. These security issues were fixed : - CVE-2018-7225: Missing input sanitization inside rfbserver.c rfbProcessClientNormalMessage() (bsc#1081493). - CVE-2016-9942: Heap-based buffer overflow in ultra.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions (bsc#1017712). - CVE-2016-9941: Heap-based buffer overflow in rfbproto.c allowed remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area (bsc#1017711). This update was imported from the SUSE:SLE-12:Update update project.
    last seen2020-06-05
    modified2018-03-30
    plugin id108743
    published2018-03-30
    reporterThis script is Copyright (C) 2018-2020 Tenable Network Security, Inc.
    sourcehttps://www.tenable.com/plugins/nessus/108743
    titleopenSUSE Security Update : LibVNCServer (openSUSE-2018-326)
  • NASL familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_64BE967AD37911E6A071001E67F15F5A.NASL
    descriptionlibvnc server reports : Two unrelated buffer overflows can be used by a malicious server to overwrite parts of the heap and crash the client (or possibly execute arbitrary code).
    last seen2020-06-01
    modified2020-06-02
    plugin id96367
    published2017-01-10
    reporterThis script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/96367
    titleFreeBSD : libvncserver -- multiple buffer overflows (64be967a-d379-11e6-a071-001e67f15f5a)

References