Amazon Linux 2 : ruby (ALAS-2025-2957)

#%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-2025-2957.
##

include('compat.inc');

if (description)
{
  script_id(243435);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/08/04");

  script_cve_id("CVE-2025-24294");

  script_name(english:"Amazon Linux 2 : ruby (ALAS-2025-2957)");

  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 ruby installed on the remote host is prior to 2.0.0.648-36. It is, therefore, affected by a vulnerability
as referenced in the ALAS2-2025-2957 advisory.

    The attack vector is a potential Denial of Service (DoS). The vulnerability is caused by an insufficient
    check on the length of a decompressed domain name within a DNS packet.An attacker can craft a malicious
    DNS packet containing a highly compressed domain name. When the resolv library parses such a packet, the
    name decompression process consumes a large amount of CPU resources, as the library does not limit the
    resulting length of the name.This resource consumption can cause the application thread to become
    unresponsive, resulting in a Denial of Service condition. (CVE-2025-24294)

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//AL2/ALAS2-2025-2957.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-2025-24294.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update ruby' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  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: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:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-24294");

  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:"2025/07/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/08/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/08/04");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ruby");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ruby-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ruby-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ruby-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ruby-irb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ruby-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:ruby-tcltk");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygem-bigdecimal");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygem-io-console");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygem-json");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygem-minitest");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygem-psych");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygem-rake");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygem-rdoc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygems");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:rubygems-devel");
  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) 2025 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':'ruby-2.0.0.648-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-2.0.0.648-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-2.0.0.648-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-debuginfo-2.0.0.648-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-debuginfo-2.0.0.648-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-debuginfo-2.0.0.648-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-devel-2.0.0.648-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-devel-2.0.0.648-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-devel-2.0.0.648-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-doc-2.0.0.648-36.amzn2.0.16', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-irb-2.0.0.648-36.amzn2.0.16', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-libs-2.0.0.648-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-libs-2.0.0.648-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-libs-2.0.0.648-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-tcltk-2.0.0.648-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-tcltk-2.0.0.648-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'ruby-tcltk-2.0.0.648-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-bigdecimal-1.2.0-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-bigdecimal-1.2.0-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-bigdecimal-1.2.0-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-io-console-0.4.2-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-io-console-0.4.2-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-io-console-0.4.2-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-json-1.7.7-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-json-1.7.7-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-json-1.7.7-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-minitest-4.3.2-36.amzn2.0.16', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-psych-2.0.0-36.amzn2.0.16', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-psych-2.0.0-36.amzn2.0.16', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-psych-2.0.0-36.amzn2.0.16', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-rake-0.9.6-36.amzn2.0.16', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygem-rdoc-4.0.0-36.amzn2.0.16', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygems-2.0.14.1-36.amzn2.0.16', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'rubygems-devel-2.0.14.1-36.amzn2.0.16', '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, "ruby / ruby-debuginfo / ruby-devel / etc");
}