Azure Linux 3.0 Security Update: syslinux (CVE-2015-7981)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(295227);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/01/22");

  script_cve_id("CVE-2015-7981");

  script_name(english:"Azure Linux 3.0 Security Update: syslinux (CVE-2015-7981)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Azure Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The version of syslinux installed on the remote Azure Linux 3.0 host is prior to tested version. It is, therefore,
affected by a vulnerability as referenced in the CVE-2015-7981 advisory.

  - The png_convert_to_rfc1123 function in png.c in libpng 1.0.x before 1.0.64, 1.2.x before 1.2.54, and 1.4.x
    before 1.4.17 allows remote attackers to obtain sensitive process memory information via crafted tIME
    chunk data in an image file, which triggers an out-of-bounds read. (CVE-2015-7981)

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://nvd.nist.gov/vuln/detail/CVE-2015-7981");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/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:N/UI:R/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2015-7981");

  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:"2015/10/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/04/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/01/22");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:syslinux");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:syslinux-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:syslinux-devel");
  script_set_attribute(attribute:"cpe", value:"x-cpe:/o:microsoft:azure_linux");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Azure Linux 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/AzureLinux/release", "Host/AzureLinux/rpm-list", "Host/cpu");

  exit(0);
}
include('rpm.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var release = get_kb_item('Host/AzureLinux/release');
if (isnull(release) || 'Azure Linux' >!< release) audit(AUDIT_OS_NOT, 'Azure Linux');
var os_ver = pregmatch(pattern: "Azure Linux ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Azure Linux');
os_ver = os_ver[1];
if (! preg(pattern:"^3([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Azure Linux 3.0', 'Azure Linux ' + os_ver);

if (!get_kb_item('Host/AzureLinux/rpm-list')) 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$" && 'aarch64' >!< cpu)
  audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Azure Linux', cpu);

var pkgs = [
    {'reference':'syslinux-6.04-11.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'syslinux-debuginfo-6.04-11.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'syslinux-devel-6.04-11.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = NULL;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = 'Azure Linux ' + package_array['release'];
  if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
  if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'syslinux / syslinux-debuginfo / syslinux-devel');
}