Amazon Linux 2023 : gawk, gawk-all-langpacks, gawk-devel (ALAS2023-2026-2035)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2023 Security Advisory ALAS2023-2026-2035.
##

include('compat.inc');

if (description)
{
  script_id(332012);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/04");

  script_cve_id("CVE-2026-40467", "CVE-2026-40468", "CVE-2026-40553");

  script_name(english:"Amazon Linux 2023 : gawk, gawk-all-langpacks, gawk-devel (ALAS2023-2026-2035)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2023 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2035 advisory.

    Use After Free vulnerability has been found in io.c program file of gawk (do_getline_redir() routine).
    This issue may lead to a crash. It affects gawk in versions 5.4.0 and below. (CVE-2026-40467)

    Integer overflow vulnerability has been found in builtin.c program file of gawk. This issue may lead to
    memory exhaustion on the hosting operating system and could be used to overwrite gawk heap metadata and
    objects with attacker-controlled bytes. It affects gawk in versions 5.4.0 and below. (CVE-2026-40468)

    Buffer overflow vulnerability has been found in extension/readdir.c program file of gawk (ftype()
    routine). This issue could be used to crash the program and potentially to achieve code execution,
    although the latter has not been confirmed to be feasible. It affects gawk in versions 5.4.0 and below.
    (CVE-2026-40553)

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

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com//AL2023/ALAS2023-2026-2035.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-40467.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-40468.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-40553.html");
  script_set_attribute(attribute:"solution", value:
"Run 'dnf update gawk --releasever 2023.12.20260803' or
  or 'dnf update --advisory ALAS2023-2026-2035 --releasever 2023.12.20260803' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/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:N/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:L/SI:L/SA:L");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-40468");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-40553");

  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:"2026/07/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/04");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:gawk");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:gawk-all-langpacks");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:gawk-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:gawk-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:gawk-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:gawk-doc");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2023");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Amazon 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_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/rpm-list");

  exit(0);
}

include("rpm2.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var alas_release = get_kb_item("Host/AmazonLinux/release");
if (isnull(alas_release) || !strlen(alas_release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d+|-\d+)", string:alas_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "-2023")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2023", "Amazon Linux " + os_ver);
}

if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var pkgs = [
    {'reference':'gawk-5.1.0-3.amzn2023.0.4', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-5.1.0-3.amzn2023.0.4', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-all-langpacks-5.1.0-3.amzn2023.0.4', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-all-langpacks-5.1.0-3.amzn2023.0.4', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-debuginfo-5.1.0-3.amzn2023.0.4', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-debuginfo-5.1.0-3.amzn2023.0.4', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-debugsource-5.1.0-3.amzn2023.0.4', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-debugsource-5.1.0-3.amzn2023.0.4', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-devel-5.1.0-3.amzn2023.0.4', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-devel-5.1.0-3.amzn2023.0.4', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'gawk-doc-5.1.0-3.amzn2023.0.4', 'release':'AL-2023', '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 = 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_HOLE,
      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, "gawk / gawk-all-langpacks / gawk-debuginfo / etc");
}