Debian dla-4638 : libgd-perl - 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-4638. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(321876);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/21");

  script_cve_id("CVE-2026-11526");

  script_name(english:"Debian dla-4638 : libgd-perl - 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 11 / 12 host has a package installed that is affected by a vulnerability as referenced in the dla-4638
advisory.

    - -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4638-1                [email protected]
    https://www.debian.org/lts/security/                 Salvatore Bonaccorso
    June 21, 2026                                 https://wiki.debian.org/LTS
    - -------------------------------------------------------------------------

    Package        : libgd-perl
    Version        : 2.73-1+deb11u1 2.76-4+deb12u1
    CVE ID         : CVE-2026-11526

    A flaw was discovered in libgd-perl, a Perl module wrapper for libgd,
    which may result in the execution of arbitrary shell commands or file
    overwrite when processing specially crafted file names.

    For Debian 11 bullseye, this problem has been fixed in version
    2.73-1+deb11u1.

    For Debian 12 bookworm, this problem has been fixed in version
    2.76-4+deb12u1.

    We recommend that you upgrade your libgd-perl packages.

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

    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

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/libgd-perl");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-11526");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bookworm/libgd-perl");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/libgd-perl");
  script_set_attribute(attribute:"solution", value:
"Upgrade the libgd-perl 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-2026-11526");

  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:"2026/06/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/21");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libgd-perl");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  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:"^(11)\.[0-9]+|^(12)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 11.0 / 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': '11.0', 'prefix': 'libgd-perl', 'reference': '2.73-1+deb11u1'},
    {'release': '12.0', 'prefix': 'libgd-perl', 'reference': '2.76-4+deb12u1'}
];

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, 'libgd-perl');
}