Vulnerabilities > CVE-2019-9895 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in multiple products

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
putty
fedoraproject
CWE-119
critical
nessus
NVD
Published: 2019-03-21
Updated: 2023-11-07

Summary

In PuTTY versions before 0.71 on Unix, a remotely triggerable buffer overflow exists in any kind of server-to-client forwarding.

Vulnerable Configurations

Part Description Count
Application
Putty
28
OS
Opengroup
1
OS
Fedoraproject
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 familyFedora Local Security Checks
    NASL idFEDORA_2019-5776DFE300.NASL
    descriptionThis is new version of putty. 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 seen2020-06-01
    modified2020-06-02
    plugin id123139
    published2019-03-27
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/123139
    titleFedora 29 : putty (2019-5776dfe300)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2019-5776dfe300.
#

include("compat.inc");

if (description)
{
  script_id(123139);
  script_version("1.4");
  script_cvs_date("Date: 2020/02/03");

  script_cve_id("CVE-2019-9894", "CVE-2019-9895", "CVE-2019-9897", "CVE-2019-9898");
  script_xref(name:"FEDORA", value:"2019-5776dfe300");

  script_name(english:"Fedora 29 : putty (2019-5776dfe300)");
  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:
"This is new version of putty.

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-2019-5776dfe300"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected putty package.");
  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:fedoraproject:fedora:putty");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:29");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/03/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/03/27");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 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:"^29([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 29", "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:"FC29", reference:"putty-0.71-1.fc29")) 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, "putty");
}
  • NASL familySuSE Local Security Checks
    NASL idOPENSUSE-2019-1113.NASL
    descriptionThis update for putty fixes the following issues : Update to new upstream release 0.71 [boo#1129633] - CVE-2019-9894: Fixed a remotely triggerable memory overwrite in RSA key exchange, which can occur before host key verification potential recycling of random numbers used in cryptography. - CVE-2019-9895: Fixed a remotely triggerable buffer overflow in any kind of server-to-client forwarding. - CVE-2019-9897: Fixed multiple denial-of-service attacks that can be triggered by writing to the terminal. - CVE-2019-9898: Fixed potential recycling of random numbers used in cryptography - CVE-2019-9896 (Windows only): Fixed hijacking by a malicious help file in the same directory as the executable - Major rewrite of the crypto code to remove cache and timing side channels.
    last seen2020-06-01
    modified2020-06-02
    plugin id123660
    published2019-04-03
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/123660
    titleopenSUSE Security Update : putty (openSUSE-2019-1113)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from openSUSE Security Update openSUSE-2019-1113.
#
# The text description of this plugin is (C) SUSE LLC.
#

include("compat.inc");

if (description)
{
  script_id(123660);
  script_version("1.2");
  script_cvs_date("Date: 2020/01/27");

  script_cve_id("CVE-2019-9894", "CVE-2019-9895", "CVE-2019-9896", "CVE-2019-9897", "CVE-2019-9898");

  script_name(english:"openSUSE Security Update : putty (openSUSE-2019-1113)");
  script_summary(english:"Check for the openSUSE-2019-1113 patch");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote openSUSE host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"This update for putty fixes the following issues :

Update to new upstream release 0.71 [boo#1129633]

  - CVE-2019-9894: Fixed a remotely triggerable memory
    overwrite in RSA key exchange, which can occur before
    host key verification potential recycling of random
    numbers used in cryptography.

  - CVE-2019-9895: Fixed a remotely triggerable buffer
    overflow in any kind of server-to-client forwarding.

  - CVE-2019-9897: Fixed multiple denial-of-service attacks
    that can be triggered by writing to the terminal.

  - CVE-2019-9898: Fixed potential recycling of random
    numbers used in cryptography

  - CVE-2019-9896 (Windows only): Fixed hijacking by a
    malicious help file in the same directory as the
    executable

  - Major rewrite of the crypto code to remove cache and
    timing side channels."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.opensuse.org/show_bug.cgi?id=1129633"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected putty 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:novell:opensuse:putty");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:putty-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:putty-debugsource");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:opensuse:15.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/04/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/04/03");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 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/SuSE/release", "Host/SuSE/rpm-list", "Host/cpu");

  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, "openSUSE");
if (release !~ "^(SUSE15\.0)$") audit(AUDIT_OS_RELEASE_NOT, "openSUSE", "15.0", release);
if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

ourarch = get_kb_item("Host/cpu");
if (!ourarch) audit(AUDIT_UNKNOWN_ARCH);
if (ourarch !~ "^(x86_64)$") audit(AUDIT_ARCH_NOT, "x86_64", ourarch);

flag = 0;

if ( rpm_check(release:"SUSE15.0", reference:"putty-0.71-lp150.9.1") ) flag++;
if ( rpm_check(release:"SUSE15.0", reference:"putty-debuginfo-0.71-lp150.9.1") ) flag++;
if ( rpm_check(release:"SUSE15.0", reference:"putty-debugsource-0.71-lp150.9.1") ) 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, "putty / putty-debuginfo / putty-debugsource");
}
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DSA-4423.NASL
    descriptionMultiple vulnerabilities were found in the PuTTY SSH client, which could result in denial of service and potentially the execution of arbitrary code. In addition, in some situations random numbers could potentially be re-used.
    last seen2020-06-01
    modified2020-06-02
    plugin id123692
    published2019-04-04
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/123692
    titleDebian DSA-4423-1 : putty - security update
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Debian Security Advisory DSA-4423. The text 
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(123692);
  script_version("1.2");
  script_cvs_date("Date: 2020/01/27");

  script_cve_id("CVE-2019-9894", "CVE-2019-9895", "CVE-2019-9897", "CVE-2019-9898");
  script_xref(name:"DSA", value:"4423");

  script_name(english:"Debian DSA-4423-1 : putty - security update");
  script_summary(english:"Checks dpkg output for the updated package");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security-related update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Multiple vulnerabilities were found in the PuTTY SSH client, which
could result in denial of service and potentially the execution of
arbitrary code. In addition, in some situations random numbers could
potentially be re-used."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security-tracker.debian.org/tracker/source-package/putty"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/stretch/putty"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.debian.org/security/2019/dsa-4423"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"Upgrade the putty packages.

For the stable distribution (stretch), these problems have been fixed
in version 0.67-3+deb9u1."
  );
  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:debian:debian_linux:putty");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:9.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/04/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/04/04");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Debian Local Security Checks");

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

  exit(0);
}


include("audit.inc");
include("debian_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian");
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;
if (deb_check(release:"9.0", prefix:"pterm", reference:"0.67-3+deb9u1")) flag++;
if (deb_check(release:"9.0", prefix:"putty", reference:"0.67-3+deb9u1")) flag++;
if (deb_check(release:"9.0", prefix:"putty-doc", reference:"0.67-3+deb9u1")) flag++;
if (deb_check(release:"9.0", prefix:"putty-tools", reference:"0.67-3+deb9u1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:deb_report_get());
  else security_hole(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2019-9E1A1CD634.NASL
    descriptionThis is new version of putty fixing few security vulnerabilities. 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 seen2020-06-01
    modified2020-06-02
    plugin id123479
    published2019-03-29
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/123479
    titleFedora 28 : putty (2019-9e1a1cd634)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2019-9e1a1cd634.
#

include("compat.inc");

if (description)
{
  script_id(123479);
  script_version("1.4");
  script_cvs_date("Date: 2020/01/27");

  script_cve_id("CVE-2019-9894", "CVE-2019-9895", "CVE-2019-9897", "CVE-2019-9898");
  script_xref(name:"FEDORA", value:"2019-9e1a1cd634");

  script_name(english:"Fedora 28 : putty (2019-9e1a1cd634)");
  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:
"This is new version of putty fixing few security vulnerabilities.

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-2019-9e1a1cd634"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected putty package.");
  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:fedoraproject:fedora:putty");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:28");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/03/29");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/03/29");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 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:"^28([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 28", "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:"FC28", reference:"putty-0.71-1.fc28")) 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, "putty");
}
  • NASL familyWindows
    NASL idPUTTY_071.NASL
    descriptionThe remote host has a version of PuTTY installed that is prior to 0.71. It is, therefore, affected by multiple vulnerabilities including: - A remotely triggerable buffer overflow in any kind of server-to-client forwarding. (CVE-2019-9895) - Potential recycling of random numbers used in cryptography. (CVE-2019-9898) - A remotely triggerable memory overwrite in RSA key exchange can occur before host key verification. (CVE-2019-9894)
    last seen2020-06-01
    modified2020-06-02
    plugin id123418
    published2019-03-27
    reporterThis script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/123418
    titlePuTTY < 0.71 Multiple Vulnerabilities
    code
    #
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(123418);
  script_version("1.2");
  script_cvs_date("Date: 2019/10/30 13:24:47");

  script_cve_id(
    "CVE-2019-9894",
    "CVE-2019-9895",
    "CVE-2019-9896",
    "CVE-2019-9897",
    "CVE-2019-9898"
  );
  script_bugtraq_id(
    107484,
    107523
  );

  script_name(english:"PuTTY < 0.71 Multiple Vulnerabilities");
  script_summary(english:"Checks the version of PuTTY.");

  script_set_attribute(attribute:"synopsis", value:
"The remote Windows host has an SSH client that is affected by
multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The remote host has a version of PuTTY installed that is prior to
0.71. It is, therefore, affected by multiple vulnerabilities
including:

  - A remotely triggerable buffer overflow in any kind of
    server-to-client forwarding. (CVE-2019-9895)

  - Potential recycling of random numbers used in cryptography.
    (CVE-2019-9898)

  - A remotely triggerable memory overwrite in RSA key exchange can
    occur before host key verification. (CVE-2019-9894)");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-auth-prompt-spoofing.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?fc188a9c");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-chm-hijack.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cd82820f");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-fd-set-overflow.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?e116cf63");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-rng-reuse.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?39988fba");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-rsa-kex-integer-overflow.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?50d03d73");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-terminal-dos-combining-chars.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?dc4b5e69");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-terminal-dos-combining-chars-double-width-gtk.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d52aebfd");
  # https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-terminal-dos-one-column-cjk.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?819250a8");
  script_set_attribute(attribute:"see_also", value:"http://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html");
  script_set_attribute(attribute:"solution", value:"Upgrade to PuTTY version 0.71 or later.");
  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:"cvss_score_source", value:"CVE-2019-9895");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/03/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/03/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:simon_tatham:putty");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows");

  script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("putty_installed.nasl");
  script_require_keys("installed_sw/PuTTY", "SMB/Registry/Enumerated");

  exit(0);
}

include("vcf.inc");

get_kb_item_or_exit("SMB/Registry/Enumerated");

app_info = vcf::get_app_info(app:"PuTTY", win_local:TRUE);

constraints = [
  { "fixed_version" : "0.71" }
];

vcf::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_HOLE);

References