Ubuntu 24.04 LTS / 26.04 LTS : kitty vulnerabilities (USN-8763-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-8763-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('compat.inc');

if (description)
{
  script_id(346239);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/16");

  script_cve_id(
    "CVE-2026-42850",
    "CVE-2026-42851",
    "CVE-2026-54055",
    "CVE-2026-54057"
  );
  script_xref(name:"IAVB", value:"2026-B-0143-S");
  script_xref(name:"IAVB", value:"2026-B-0230");
  script_xref(name:"USN", value:"8763-1");

  script_name(english:"Ubuntu 24.04 LTS / 26.04 LTS : kitty vulnerabilities (USN-8763-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 24.04 LTS / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as
referenced in the USN-8763-1 advisory.

    It was discovered that kitty incorrectly escaped error messages when handling specially crafted terminal
    escape sequences. A remote attacker could possibly use this issue to execute arbitrary commands.
    (CVE-2026-42850)

    It was discovered that kitty incorrectly handled remote edit requests in terminal output. An attacker
    could possibly use this issue to execute arbitrary code with the user's privileges. (CVE-2026-42851)

    Thai Son Dinh and Nguyen Huy Vu Dung discovered that kitty incorrectly handled destination paths in its
    file transmission protocol. A local attacker could possibly use this issue to overwrite arbitrary files
    with the user's privileges. (CVE-2026-54055)

    It was discovered that kitty incorrectly sanitized responses to color queries. An attacker could possibly
    use this issue to execute arbitrary commands with the user's privileges. This issue only affected Ubuntu
    26.04 LTS. (CVE-2026-54057)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/notices/USN-8763-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected kitty, kitty-shell-integration and / or kitty-terminfo packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:P");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-42850");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/06/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/09/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/16");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:24.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:26.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:kitty");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:kitty-shell-integration");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:kitty-terminfo");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Ubuntu Local Security Checks");

  script_copyright(english:"Ubuntu Security Notice (C) 2026 Canonical, Inc. / NASL script (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}

include('debian_package.inc');

if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('24.04' >< os_release || '26.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 24.04 / 26.04', 'Ubuntu ' + os_release);
if ( ! get_kb_item('Host/Debian/dpkg-l') ) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);

var pkgs = [
    {'osver': '24.04', 'pkgname': 'kitty', 'pkgver': '0.32.2-1ubuntu0.4+esm2', 'cves': ['CVE-2026-42850', 'CVE-2026-42851', 'CVE-2026-54055']},
    {'osver': '24.04', 'pkgname': 'kitty-shell-integration', 'pkgver': '0.32.2-1ubuntu0.4+esm2', 'cves': ['CVE-2026-42850', 'CVE-2026-42851', 'CVE-2026-54055']},
    {'osver': '24.04', 'pkgname': 'kitty-terminfo', 'pkgver': '0.32.2-1ubuntu0.4+esm2', 'cves': ['CVE-2026-42850', 'CVE-2026-42851', 'CVE-2026-54055']},
    {'osver': '26.04', 'pkgname': 'kitty', 'pkgver': '0.45.0-1ubuntu0.1~esm2', 'cves': ['CVE-2026-42850', 'CVE-2026-42851', 'CVE-2026-54055', 'CVE-2026-54057']},
    {'osver': '26.04', 'pkgname': 'kitty-shell-integration', 'pkgver': '0.45.0-1ubuntu0.1~esm2', 'cves': ['CVE-2026-42850', 'CVE-2026-42851', 'CVE-2026-54055', 'CVE-2026-54057']},
    {'osver': '26.04', 'pkgname': 'kitty-terminfo', 'pkgver': '0.45.0-1ubuntu0.1~esm2', 'cves': ['CVE-2026-42850', 'CVE-2026-42851', 'CVE-2026-54055', 'CVE-2026-54057']}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var osver = NULL;
  var pkgname = NULL;
  var pkgver = NULL;
  if (!empty_or_null(package_array['osver'])) osver = package_array['osver'];
  if (!empty_or_null(package_array['pkgname'])) pkgname = package_array['pkgname'];
  if (!empty_or_null(package_array['pkgver'])) pkgver = package_array['pkgver'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (osver && pkgname && pkgver) {
    if (deb_check(release:osver, prefix:pkgname, reference:pkgver, cves:cves)) flag++;
  }
}

if (flag)
{
  var extra = '';
  extra += ubuntu_report_get();
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : extra
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'kitty / kitty-shell-integration / kitty-terminfo');
}