Debian dla-4573 : libpng-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 dla-4573. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(313514);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/14");

  script_cve_id("CVE-2026-34757");

  script_name(english:"Debian dla-4573 : libpng-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 11 host has packages installed that are affected by a vulnerability as referenced in the dla-4573
advisory.

    -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4573-1                [email protected]
    https://www.debian.org/lts/security/                         Tobias Frost
    May 09, 2026                                  https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : libpng1.6
    Version        : 1.6.37-3+deb11u4
    CVE ID         : CVE-2026-34757
    Debian Bug     : 1133051

    A security vulnerability has been discovered in libpng, a library
    implementing an interface for reading and writing PNG (Portable Network
    Graphics) files, which could leading to corrupted chunk data and potential
    heap information disclosure.

    For Debian 11 bullseye, this problem has been fixed in version
    1.6.37-3+deb11u4.

    We recommend that you upgrade your libpng1.6 packages.

    For the detailed security status of libpng1.6 please refer to its security
    tracker page at:
    https://security-tracker.debian.org/tracker/libpng1.6

    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/libpng1.6");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-34757");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/libpng1.6");
  script_set_attribute(attribute:"solution", value:
"Upgrade the libpng-dev packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:P/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:L/AC:L/PR:L/UI:N/S:U/C:L/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-2026-34757");

  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:"2026/04/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/05/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/05/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libpng-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libpng-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libpng16-16");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libpng16-16-udeb");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  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]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 11.0', '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': 'libpng-dev', 'reference': '1.6.37-3+deb11u4'},
    {'release': '11.0', 'prefix': 'libpng-tools', 'reference': '1.6.37-3+deb11u4'},
    {'release': '11.0', 'prefix': 'libpng16-16', 'reference': '1.6.37-3+deb11u4'},
    {'release': '11.0', 'prefix': 'libpng16-16-udeb', 'reference': '1.6.37-3+deb11u4'}
];

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_NOTE,
    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, 'libpng-dev / libpng-tools / libpng16-16 / libpng16-16-udeb');
}