Amazon Linux 2 : ipa (ALAS-2026-4008)

#%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-2026-4008.
##

include('compat.inc');

if (description)
{
  script_id(371774);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/24");

  script_cve_id("CVE-2026-73196", "CVE-2026-73199");

  script_name(english:"Amazon Linux 2 : ipa (ALAS-2026-4008)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2026-4008 advisory.

    A flaw was found in FreeIPA. A low-privilege authenticated user can exploit this vulnerability by
    submitting an oversized One-Time Password (OTP) key value. This oversized key is then decoded and re-
    encoded without proper size limits, consuming excessive CPU and memory resources. This can lead to a
    denial of service, degrading the availability of the IPA service. (CVE-2026-73196)

    A flaw was found in the `ipa-enrollment` SLAPI plugin. A remote authenticated client can exploit a null
    pointer dereference vulnerability by sending a malformed Lightweight Directory Access Protocol (LDAP)
    extended operation. By omitting the request value for the `JOIN_OID` in the `ipa-enrollment` extended
    operation, an attacker can trigger a server crash, potentially causing a denial of service.
    (CVE-2026-73199)

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/ALAS2-2026-4008.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-2026-73196.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-73199.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update ipa' or
  or 'yum update --advisory ALAS2-2026-4008' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:N/I:N/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:L/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-73196");

  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:"2026/08/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/24");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/24");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-client-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-python-compat");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-server-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-server-dns");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ipa-server-trust-ad");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python2-ipaclient");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python2-ipalib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python2-ipaserver");
  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_info2.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 != "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':'ipa-client-4.6.8-5.amzn2.17.10', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-client-4.6.8-5.amzn2.17.10', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-client-4.6.8-5.amzn2.17.10', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-client-common-4.6.8-5.amzn2.17.10', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-common-4.6.8-5.amzn2.17.10', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-debuginfo-4.6.8-5.amzn2.17.10', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-debuginfo-4.6.8-5.amzn2.17.10', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-debuginfo-4.6.8-5.amzn2.17.10', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-python-compat-4.6.8-5.amzn2.17.10', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-4.6.8-5.amzn2.17.10', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-4.6.8-5.amzn2.17.10', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-4.6.8-5.amzn2.17.10', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-common-4.6.8-5.amzn2.17.10', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-dns-4.6.8-5.amzn2.17.10', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-trust-ad-4.6.8-5.amzn2.17.10', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-trust-ad-4.6.8-5.amzn2.17.10', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ipa-server-trust-ad-4.6.8-5.amzn2.17.10', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python2-ipaclient-4.6.8-5.amzn2.17.10', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python2-ipalib-4.6.8-5.amzn2.17.10', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python2-ipaserver-4.6.8-5.amzn2.17.10', '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_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, "ipa-client / ipa-client-common / ipa-common / etc");
}