Debian dsa-6529 : libwebsockets-dev - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dsa-6529. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(351210);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/29");

  script_cve_id("CVE-2026-19773");

  script_name(english:"Debian dsa-6529 : libwebsockets-dev - security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing a security-related update.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 13 host has packages installed that are affected by a vulnerability as referenced in the dsa-6529
advisory.

    - -------------------------------------------------------------------------
    Debian Security Advisory DSA-6529-1                   [email protected]
    https://www.debian.org/security/                       Moritz Muehlenhoff
    September 29, 2026                    https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : libwebsockets
    CVE ID         : CVE-2026-19773

    It was discovered that missing input validation in the hpack path
    header parser of libwebsockets could result in denial of service or
    potentially the execution of arbitrary code.

    For the stable distribution (trixie), this problem has been fixed in
    version 4.3.5-1+deb13u3.

    We recommend that you upgrade your libwebsockets packages.

    For the detailed security status of libwebsockets please refer to
    its security tracker page at:
    https://security-tracker.debian.org/tracker/libwebsockets

    Further information about Debian Security Advisories, how to apply
    these updates to your system and frequently asked questions can be
    found at: https://www.debian.org/security/

    Mailing list: [email protected]

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

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://security-tracker.debian.org/tracker/source-package/libwebsockets
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?adc7ba17");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-19773");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/trixie/libwebsockets");
  script_set_attribute(attribute:"solution", value:
"Upgrade the libwebsockets-dev 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: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-2026-19773");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/09/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/09/29");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/29");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libwebsockets-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libwebsockets-evlib-ev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libwebsockets-evlib-glib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libwebsockets-evlib-uv");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libwebsockets-test-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libwebsockets-test-server-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libwebsockets19t64");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:13.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/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);
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);

var debian_release = get_kb_item('Host/Debian/release');
if ( isnull(debian_release) ) audit(AUDIT_OS_NOT, 'Debian');
debian_release = chomp(debian_release);
if (! preg(pattern:"^(13)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 13.0', 'Debian ' + debian_release);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Debian', cpu);

var pkgs = [
    {'release': '13.0', 'prefix': 'libwebsockets-dev', 'reference': '4.3.5-1+deb13u3'},
    {'release': '13.0', 'prefix': 'libwebsockets-evlib-ev', 'reference': '4.3.5-1+deb13u3'},
    {'release': '13.0', 'prefix': 'libwebsockets-evlib-glib', 'reference': '4.3.5-1+deb13u3'},
    {'release': '13.0', 'prefix': 'libwebsockets-evlib-uv', 'reference': '4.3.5-1+deb13u3'},
    {'release': '13.0', 'prefix': 'libwebsockets-test-server', 'reference': '4.3.5-1+deb13u3'},
    {'release': '13.0', 'prefix': 'libwebsockets-test-server-common', 'reference': '4.3.5-1+deb13u3'},
    {'release': '13.0', 'prefix': 'libwebsockets19t64', 'reference': '4.3.5-1+deb13u3'}
];

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

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : deb_report_get()
  );
  exit(0);
}
else
{
  var tested = deb_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libwebsockets-dev / libwebsockets-evlib-ev / libwebsockets-evlib-glib / etc');
}