Amazon Linux 2 : python3-tornado, --advisory ALAS2-2025-3109 (ALAS-2025-3109)

#%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-2025-3109.
##

include('compat.inc');

if (description)
{
  script_id(281825);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/30");

  script_cve_id("CVE-2025-67724", "CVE-2025-67725", "CVE-2025-67726");
  script_xref(name:"IAVB", value:"2026-B-0009-S");

  script_name(english:"Amazon Linux 2 : python3-tornado, --advisory ALAS2-2025-3109 (ALAS-2025-3109)");

  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 python3-tornado installed on the remote host is prior to 5.0.2-4. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2025-3109 advisory.

    Tornado is a Python web framework and asynchronous networking library. In versions 6.5.2 and below, the
    supplied reason phrase is used unescaped in HTTP headers (where it could be used for header injection) or
    in HTML in the default error page (where it could be used for XSS) and can be exploited by passing
    untrusted or malicious data into the reason argument. Used by both RequestHandler.set_status and
    tornado.web.HTTPError, the argument is designed to allow applications to pass custom reason phrases (the
    Not Found in HTTP/1.1 404 Not Found) to the HTTP status line (mainly for non-standard status codes).
    This issue is fixed in version 6.5.3. (CVE-2025-67724)

    Tornado is a Python web framework and asynchronous networking library. In versions 6.5.2 and below, a
    single maliciously crafted HTTP request can block the server's event loop for an extended period, caused
    by the HTTPHeaders.add method. The function accumulates values using string concatenation when the same
    header name is repeated, causing a Denial of Service (DoS).  Due to Python string immutability, each
    concatenation copies the entire string, resulting in O(n2) time complexity. The severity can vary from
    high if max_header_size has been increased from its default, to low if it has its default value of 64KB.
    This issue is fixed in version 6.5.3. (CVE-2025-67725)

    Tornado is a Python web framework and asynchronous networking library. Versions 6.5.2 and below use an
    inefficient algorithm when parsing parameters for HTTP header values, potentially causing a DoS. The
    _parseparam function in httputil.py is used to parse specific HTTP header values, such as those in
    multipart/form-data and repeatedly calls string.count() within a nested loop while processing quoted
    semicolons. If an attacker sends a request with a large number of maliciously crafted parameters in a
    Content-Disposition header, the server's CPU usage increases quadratically (O(n2)) during parsing. Due to
    Tornado's single event loop architecture, a single malicious request can cause the entire server to become
    unresponsive for an extended period. This issue is fixed in version 6.5.3. (CVE-2025-67726)

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/ALAS2-2025-3109.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-2025-67724.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2025-67725.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2025-67726.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update python3-tornado' or
  or 'yum update --advisory ALAS2-2025-3109' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/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:R/S:C/C:L/I:L/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-2025-67724");

  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:"2025/12/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/01/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/01/05");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-tornado");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-tornado-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-tornado-doc");
  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("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':'python3-tornado-5.0.2-4.amzn2.0.6', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-5.0.2-4.amzn2.0.6', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-5.0.2-4.amzn2.0.6', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-debuginfo-5.0.2-4.amzn2.0.6', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-debuginfo-5.0.2-4.amzn2.0.6', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-debuginfo-5.0.2-4.amzn2.0.6', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-doc-5.0.2-4.amzn2.0.6', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-doc-5.0.2-4.amzn2.0.6', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python3-tornado-doc-5.0.2-4.amzn2.0.6', '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_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, "python3-tornado / python3-tornado-debuginfo / python3-tornado-doc");
}