Amazon Linux 2 : libsolv, --advisory ALAS2-2026-3338 (ALAS-2026-3338)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALAS-2026-3338.
##

include('compat.inc');

if (description)
{
  script_id(319816);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/08");

  script_cve_id("CVE-2026-9149", "CVE-2026-9150", "CVE-2026-48864");

  script_name(english:"Amazon Linux 2 : libsolv, --advisory ALAS2-2026-3338 (ALAS-2026-3338)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of libsolv installed on the remote host is prior to 0.6.34-4. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2026-3338 advisory.

    A flaw was found in libsolv. This heap buffer overflow occurs during the decompression of attacker-
    controlled compressed data within `.solv` files due to insufficient input validation. An attacker can
    provide a specially crafted `.solv` file, which, when processed by a vulnerable application, can lead to
    out-of-bounds memory access. This could result in information disclosure, alteration of program execution,
    or a denial of service. (CVE-2026-48864)

    A flaw was found in libsolv. This heap buffer overflow vulnerability occurs when a victim processes a
    specially crafted .solv file containing negative size values in the repo_add_solv function. This leads to
    an undersized memory allocation and a subsequent out-of-bounds write. An attacker could exploit this to
    cause a denial of service (DoS). (CVE-2026-9149)

    A flaw was found in libsolv. This stack-based buffer overflow vulnerability occurs in libsolv's Debian
    metadata parser when processing specially crafted Debian repository metadata. An attacker could exploit
    this by providing malicious SHA384 or SHA512 checksum tags, leading to memory corruption and a denial of
    service (DoS) in the affected system. (CVE-2026-9150)

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//AL2/ALAS2-2026-3338.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-2026-48864.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-9149.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-9150.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update libsolv' or
  or 'yum update --advisory ALAS2-2026-3338' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
  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: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-2026-9149");

  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:"2026/05/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libsolv");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libsolv-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libsolv-demo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libsolv-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libsolv-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python2-solv");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
  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("rpm.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 != "2")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}

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

var pkgs = [
    {'reference':'libsolv-0.6.34-4.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-0.6.34-4.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-0.6.34-4.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-debuginfo-0.6.34-4.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-debuginfo-0.6.34-4.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-debuginfo-0.6.34-4.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-demo-0.6.34-4.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-demo-0.6.34-4.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-demo-0.6.34-4.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-devel-0.6.34-4.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-devel-0.6.34-4.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-devel-0.6.34-4.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-tools-0.6.34-4.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-tools-0.6.34-4.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libsolv-tools-0.6.34-4.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python2-solv-0.6.34-4.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python2-solv-0.6.34-4.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python2-solv-0.6.34-4.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', '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, "libsolv / libsolv-debuginfo / libsolv-demo / etc");
}