Debian dla-4842 : haproxy - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dla-4842. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(366978);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/18");

  script_cve_id("CVE-2026-33555");
  script_xref(name:"IAVB", value:"2026-B-0103");

  script_name(english:"Debian dla-4842 : haproxy - 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 12 host has packages installed that are affected by a vulnerability as referenced in the dla-4842
advisory.

    -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4842-1                [email protected]
    https://www.debian.org/lts/security/               Santiago Ruano Rincn
    October 18, 2026                              https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : haproxy
    Version        : 2.6.12-1+deb12u4
    CVE ID         : CVE-2026-33555, not yet available

    Three vulnerabilities were discovered in HAProxy, a fast and reliable load
    balancing reverse proxy, which could result in denial of service or HTTP
    request smuggling.

    CVE-2026-33555

        Martino Spagnuolo reported that the HTTP/3 parsing code in HAProxy, a fast
        and reliable load balancing reverse proxy, does not properly validate the
        received body size and the announced content-length header, which may
        result in HTTP request smuggling.  It is to note that these features are
        not enabled by default in the binary packages distributed with Debian
        bookworm.

    Two other vulnerabilities, that may result in denial of service, don't have a
    CVE assigned yet.

    For Debian 12 bookworm, these problems have been fixed in version
    2.6.12-1+deb12u4.

    We recommend that you upgrade your haproxy packages.

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

    Further information about Debian LTS security advisories, how to apply
    these updates to your system and frequently asked questions can be
    found at: https://wiki.debian.org/LTS
    Attachment:
    signature.asc
    Description: PGP signature

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.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/source-package/haproxy");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-33555");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bookworm/haproxy");
  script_set_attribute(attribute:"solution", value:
"Upgrade the haproxy packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  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:N/S:C/C:N/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-33555");

  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:"2026/04/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/18");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:haproxy");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:haproxy-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:vim-haproxy");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  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:"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_info2.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:"^(12)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 12.0', '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': '12.0', 'prefix': 'haproxy', 'reference': '2.6.12-1+deb12u4'},
    {'release': '12.0', 'prefix': 'haproxy-doc', 'reference': '2.6.12-1+deb12u4'},
    {'release': '12.0', 'prefix': 'vim-haproxy', 'reference': '2.6.12-1+deb12u4'}
];

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_WARNING,
    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, 'haproxy / haproxy-doc / vim-haproxy');
}