Vulnerabilities > CVE-2020-11046 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in multiple products

047910
CVSS 2.2 - LOW
Attack vector
NETWORK
Attack complexity
HIGH
Privileges required
HIGH
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
LOW
network
high complexity
freerdp
canonical
debian
CWE-119
nessus
NVD
Published: 2020-05-07
Updated: 2023-10-24

Summary

In FreeRDP after 1.0 and before 2.0.0, there is a stream out-of-bounds seek in update_read_synchronize that could lead to a later out-of-bounds read.

Vulnerable Configurations

Part Description Count
Application
Freerdp
16
OS
Canonical
4
OS
Debian
2

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-4379-1.NASL
    descriptionIt was discovered that FreeRDP incorrectly handled certain memory operations. A remote attacker could use this issue to cause FreeRDP to crash, resulting in a denial of service, or possibly exeucte arbitrary code. 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 seen2020-06-06
    modified2020-06-02
    plugin id137045
    published2020-06-02
    reporterUbuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137045
    titleUbuntu 18.04 LTS / 19.10 / 20.04 : freerdp2 vulnerabilities (USN-4379-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4379-1. 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(137045);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/05");

  script_cve_id("CVE-2018-1000852", "CVE-2019-17177", "CVE-2020-11042", "CVE-2020-11044", "CVE-2020-11045", "CVE-2020-11046", "CVE-2020-11047", "CVE-2020-11048", "CVE-2020-11049", "CVE-2020-11058", "CVE-2020-11521", "CVE-2020-11522", "CVE-2020-11523", "CVE-2020-11524", "CVE-2020-11525", "CVE-2020-11526", "CVE-2020-13396", "CVE-2020-13397", "CVE-2020-13398");
  script_xref(name:"USN", value:"4379-1");

  script_name(english:"Ubuntu 18.04 LTS / 19.10 / 20.04 : freerdp2 vulnerabilities (USN-4379-1)");
  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:
"It was discovered that FreeRDP incorrectly handled certain memory
operations. A remote attacker could use this issue to cause FreeRDP to
crash, resulting in a denial of service, or possibly exeucte arbitrary
code.

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/4379-1/"
  );
  script_set_attribute(
    attribute:"solution",
    value:
"Update the affected libfreerdp-client2-2, libfreerdp-server2-2 and /
or libfreerdp2-2 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:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp-client2-2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp-server2-2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp2-2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.10");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/12/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/06/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/02");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 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:"^(18\.04|19\.10|20\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 18.04 / 19.10 / 20.04", "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:"18.04", pkgname:"libfreerdp-client2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.18.04.1")) flag++;
if (ubuntu_check(osver:"18.04", pkgname:"libfreerdp-server2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.18.04.1")) flag++;
if (ubuntu_check(osver:"18.04", pkgname:"libfreerdp2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.18.04.1")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"libfreerdp-client2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.19.10.1")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"libfreerdp-server2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.19.10.1")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"libfreerdp2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.19.10.1")) flag++;
if (ubuntu_check(osver:"20.04", pkgname:"libfreerdp-client2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.20.04.1")) flag++;
if (ubuntu_check(osver:"20.04", pkgname:"libfreerdp-server2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.20.04.1")) flag++;
if (ubuntu_check(osver:"20.04", pkgname:"libfreerdp2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.20.04.1")) 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, "libfreerdp-client2-2 / libfreerdp-server2-2 / libfreerdp2-2");
}
  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-4382-1.NASL
    descriptionIt was discovered that FreeRDP incorrectly handled certain memory operations. A remote attacker could use this issue to cause FreeRDP to crash, resulting in a denial of service, or possibly execute arbitrary code. 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 seen2020-06-10
    modified2020-06-05
    plugin id137178
    published2020-06-05
    reporterUbuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137178
    titleUbuntu 16.04 LTS : freerdp vulnerabilities (USN-4382-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4382-1. 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(137178);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/09");

  script_cve_id("CVE-2020-11042", "CVE-2020-11045", "CVE-2020-11046", "CVE-2020-11048", "CVE-2020-11049", "CVE-2020-11058", "CVE-2020-11521", "CVE-2020-11522", "CVE-2020-11523", "CVE-2020-11525", "CVE-2020-11526", "CVE-2020-13396", "CVE-2020-13397", "CVE-2020-13398");
  script_xref(name:"USN", value:"4382-1");

  script_name(english:"Ubuntu 16.04 LTS : freerdp vulnerabilities (USN-4382-1)");
  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:
"It was discovered that FreeRDP incorrectly handled certain memory
operations. A remote attacker could use this issue to cause FreeRDP to
crash, resulting in a denial of service, or possibly execute arbitrary
code.

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/4382-1/"
  );
  script_set_attribute(
    attribute:"solution",
    value:
"Update the affected libfreerdp-client1.1, libfreerdp-common1.1.0 and /
or libfreerdp-core1.1 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:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp-client1.1");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp-common1.1.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp-core1.1");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/05/07");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/06/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/05");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 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:"^(16\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 16.04", "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:"16.04", pkgname:"libfreerdp-client1.1", pkgver:"1.1.0~git20140921.1.440916e+dfsg1-5ubuntu1.4")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"libfreerdp-common1.1.0", pkgver:"1.1.0~git20140921.1.440916e+dfsg1-5ubuntu1.4")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"libfreerdp-core1.1", pkgver:"1.1.0~git20140921.1.440916e+dfsg1-5ubuntu1.4")) 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, "libfreerdp-client1.1 / libfreerdp-common1.1.0 / libfreerdp-core1.1");
}

References