Amazon Linux 2023 : freerdp, freerdp-devel, freerdp-libs (ALAS2023-2026-2053)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2023 Security Advisory ALAS2023-2026-2053.
##

include('compat.inc');

if (description)
{
  script_id(337245);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/18");

  script_cve_id("CVE-2026-64620", "CVE-2026-64621");

  script_name(english:"Amazon Linux 2023 : freerdp, freerdp-devel, freerdp-libs (ALAS2023-2026-2053)");

  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 ALAS2023-2026-2053 advisory.

    FreeRDP before 3.28.0 (affected <=3.27.1) contains a heap-based buffer overflow in crypto_rsa_common()
    (libfreerdp/crypto/crypto.c). The function writes the modular-exponentiation result into the caller's
    output buffer via BN_bn2bin() and only afterward checks output_length > out_length, so out-of-bounds bytes
    are written before the bounds check. On the server side, when a client selects RDP Standard Security, the
    encrypted client random is decrypted into a fixed 32-byte buffer. Because the server publishes its RSA
    public key, an unauthenticated attacker can forge a ciphertext whose decrypted value is up to the full
    modulus length (e.g. 256 bytes for RSA-2048), overflowing the 32-byte heap buffer by up to ~224 attacker-
    controlled bytes pre-authentication, resulting in denial of service. (CVE-2026-64620)

    FreeRDP before 3.28.0 (affected 3.x through 3.27.1) contains a double-free vulnerability in
    freerdp_client_rdp_file_apply_to_settings() (client/common/file.c) when parsing the selectedmonitors field
    of a .rdp connection file. The MonitorIds array is allocated through the settings object, and a raw non-
    owning pointer to it is freed on the strtoul error path without clearing settings->MonitorIds, leaving it
    dangling; at teardown freerdp_settings_free() frees the same buffer again. An attacker who convinces a
    victim to open a crafted .rdp file with oversized monitor tokens can trigger a size-controlled double-free
    in any FreeRDP CLI client (xfreerdp/sdl-freerdp/wlfreerdp) in the default configuration. (CVE-2026-64621)

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/ALAS2023-2026-2053.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-2026-64620.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-64621.html");
  script_set_attribute(attribute:"solution", value:
"Run 'dnf update freerdp --releasever 2023.12.20260817' or
  or 'dnf update --advisory ALAS2023-2026-2053 --releasever 2023.12.20260817' 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:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:P");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-64620");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-64621");

  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:"2026/07/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/18");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp-libs-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:freerdp-server-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libwinpr");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libwinpr-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libwinpr-devel");
  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':'freerdp-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-debugsource-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-debugsource-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-devel-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-devel-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-libs-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-libs-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-libs-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-libs-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-server-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-server-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-server-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'freerdp-server-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libwinpr-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libwinpr-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libwinpr-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libwinpr-debuginfo-3.6.3-1.amzn2023.0.14', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libwinpr-devel-3.6.3-1.amzn2023.0.14', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libwinpr-devel-3.6.3-1.amzn2023.0.14', '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_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, "freerdp / freerdp-debuginfo / freerdp-debugsource / etc");
}