Amazon Linux 2023 : PackageKit, PackageKit-command-not-found, PackageKit-cron (ALAS2023-2026-1639)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2023 Security Advisory ALAS2023-2026-1639.
##

include('compat.inc');

if (description)
{
  script_id(315642);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/20");

  script_cve_id("CVE-2026-41651");

  script_name(english:"Amazon Linux 2023 : PackageKit, PackageKit-command-not-found, PackageKit-cron (ALAS2023-2026-1639)");

  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 a vulnerability as referenced in the ALAS2023-2026-1639 advisory.

    PackageKit is a a D-Bus abstraction layer that allows the user to manage packages in a secure way using a
    cross-distro, cross-architecture API. PackageKit between and including versions 1.0.2 and 1.3.4 is
    vulnerable to a time-of-check time-of-use (TOCTOU) race condition on transaction flags that allows
    unprivileged users to install packages as root and thus leads to a local privilege escalation. This is
    patched in version 1.3.5. A local unprivileged user can install arbitrary RPM packages as root, including
    executing RPM scriptlets, without authentication. The vulnerability is a TOCTOU race condition on
    `transaction->cached_transaction_flags` combined with a silent state-machine guard that discards illegal
    backward transitions while leaving corrupted flags in place. Three bugs exist in `src/pk-transaction.c`:
    1. Unconditional flag overwrite (line 4036): `InstallFiles()` writes caller-supplied flags to
    `transaction->cached_transaction_flags` without checking whether the transaction has already been
    authorized/started. A second call blindly overwrites the flags even while the transaction is RUNNING. 2.
    Silent state-transition rejection (lines 873-882): `pk_transaction_set_state()` silently discards backward
    state transitions (e.g. `RUNNING` - `WAITING_FOR_AUTH`) but the flag overwrite at step 1 already happened.
    The transaction continues running with corrupted flags. 3. Late flag read at execution time (lines
    2273-2277): The scheduler's idle callback reads cached_transaction_flags at dispatch time, not at
    authorization time. If flags were overwritten between authorization and execution, the backend sees the
    attacker's flags. (CVE-2026-41651)

Tenable has extracted the preceding description block directly from the tested product 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://alas.aws.amazon.com//AL2023/ALAS2023-2026-1639.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-2026-41651.html");
  script_set_attribute(attribute:"solution", value:
"Run 'dnf update PackageKit --releasever 2023.11.20260511' or
  or 'dnf update --advisory ALAS2023-2026-1639 --releasever 2023.11.20260511' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C");
  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:C/C:H/I:H/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-2026-41651");

  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:"2026/04/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/05/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/05/20");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-command-not-found");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-command-not-found-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-cron");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-glib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-glib-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-glib-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-gtk3-module");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:PackageKit-gtk3-module-debuginfo");
  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("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 != "-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':'PackageKit-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-command-not-found-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-command-not-found-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-command-not-found-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-command-not-found-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-cron-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-cron-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-debugsource-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-debugsource-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-glib-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-glib-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-glib-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-glib-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-glib-devel-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-glib-devel-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-gtk3-module-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-gtk3-module-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-gtk3-module-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'PackageKit-gtk3-module-debuginfo-1.2.8-2.amzn2023.0.2', 'cpu':'x86_64', '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_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, "PackageKit / PackageKit-command-not-found / PackageKit-command-not-found-debuginfo / etc");
}