Amazon Linux 2 : bind, --advisory ALAS2-2026-3854 (ALAS-2026-3854)

#%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-2026-3854.
##

include('compat.inc');

if (description)
{
  script_id(332027);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/04");

  script_cve_id(
    "CVE-2026-10723",
    "CVE-2026-11622",
    "CVE-2026-11721",
    "CVE-2026-13204",
    "CVE-2026-13321"
  );
  script_xref(name:"IAVA", value:"2026-A-0764");

  script_name(english:"Amazon Linux 2 : bind, --advisory ALAS2-2026-3854 (ALAS-2026-3854)");

  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 bind installed on the remote host is prior to 9.11.4-26.P2. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2026-3854 advisory.

    BIND may accept incorrect child-zone NSEC3 records as valid, which could allow an attacker to forge
    authenticated NXDOMAIN responses.This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through
    9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
    (CVE-2026-10723)

    A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can
    suffer from runaway memory usage. The attacker needs to be able to send queries faster than the resolver
    can perform validation. The increased memory usage can be orders of magnitude beyond the limit configured
    in the `max-cache-size` parameter.This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0
    through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
    (CVE-2026-11622)

    It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of
    labels than the zone in which the RRSIG is contained. This causes `named` to produce a wildcard name for a
    zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to
    have any effect, the resolver under attack must have set `synth-from-dnssec yes;` (which is the
    default).This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through
    9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-11721)

    If a provably insecure domain is covered by both an NSEC and NSEC3 record at the parent, and there exist
    an RRSIG for only one of these types, then BIND may exit unexpectedly with an assertion while validating
    this proof.This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0
    through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-13204)

    The BIND resolver accepts validly-signed NSEC records where the Next Domain Name field points outside
    the signer's zone.This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24,
    9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-13321)

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/ALAS2-2026-3854.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-2026-10723.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-11622.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-11721.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-13204.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-13321.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update bind' or
  or 'yum update --advisory ALAS2-2026-3854' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:C/A:N");
  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:C/C:N/I:H/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-13321");

  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:"2026/07/22");
  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:bind");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-chroot");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-export-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-export-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-libs-lite");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-license");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-lite-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-pkcs11");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-pkcs11-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-pkcs11-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-pkcs11-utils");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-sdb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-sdb-chroot");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bind-utils");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  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 != "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':'bind-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-chroot-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-chroot-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-chroot-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-debuginfo-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-debuginfo-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-debuginfo-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-export-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-export-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-export-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-export-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-export-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-export-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-libs-lite-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-libs-lite-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-libs-lite-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-license-9.11.4-26.P2.amzn2.13.17', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-lite-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-lite-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-lite-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-devel-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-libs-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-utils-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-utils-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-pkcs11-utils-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-sdb-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-sdb-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-sdb-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-sdb-chroot-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-sdb-chroot-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-sdb-chroot-9.11.4-26.P2.amzn2.13.17', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-utils-9.11.4-26.P2.amzn2.13.17', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-utils-9.11.4-26.P2.amzn2.13.17', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bind-utils-9.11.4-26.P2.amzn2.13.17', '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, "bind / bind-chroot / bind-debuginfo / etc");
}