CentOS Linux 7 [TuxCare] Security Update: python3 / python3-debug / python3-devel / python3-idle / etc Multiple Vulnerabilities (CENTOS7:CLSA-2026:1777970333)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(359950);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/01");

  script_cve_id(
    "CVE-2021-3733",
    "CVE-2021-4189",
    "CVE-2021-23336",
    "CVE-2022-37454",
    "CVE-2022-48566",
    "CVE-2023-27043",
    "CVE-2026-1299"
  );
  script_xref(name:"CLSA", value:"2026:1777970333");

  script_name(english:"CentOS Linux 7 [TuxCare] Security Update: python3 / python3-debug / python3-devel / python3-idle / etc Multiple Vulnerabilities (CENTOS7:CLSA-2026:1777970333)");

  script_set_attribute(attribute:"synopsis", value:
"The CentOS Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The CentOS Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the
TuxCare CENTOS7:CLSA-2026:1777970333 advisory.

  - The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before
    3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and
    urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query
    parameters using a semicolon (;), they can cause a difference in the interpretation of the request between
    the proxy (running with default configuration) and the server. This can result in malicious requests being
    cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and
    therefore would not include it in a cache key of an unkeyed parameter. (CVE-2021-23336)

  - There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP
    server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of
    Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the
    server to the client. The greatest threat that this flaw poses is to application availability.
    (CVE-2021-3733)

  - A flaw was found in Python, specifically in the FTP (File Transfer Protocol) client library in PASV
    (passive) mode. The issue is how the FTP client trusts the host from the PASV response by default. This
    flaw allows an attacker to set up a malicious FTP server that can trick FTP clients into connecting back
    to a given IP address and port. This vulnerability could lead to FTP client scanning ports, which
    otherwise would not have been possible. (CVE-2021-4189)

  - The Keccak XKCP SHA-3 reference implementation before fdc6fef has an integer overflow and resultant buffer
    overflow that allows attackers to execute arbitrary code or eliminate expected cryptographic properties.
    This occurs in the sponge function interface. (CVE-2022-37454)

  - An issue was discovered in compare_digest in Lib/hmac.py in Python through 3.9.1. Constant-time-defeating
    optimisations were possible in the accumulator variable in hmac.compare_digest. (CVE-2022-48566)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://security.tuxcare.com/csaf/v2/els_os/centos7els/advisories/2026/clsa-2026_1777970333.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?633121d2");
  script_set_attribute(attribute:"see_also", value:"https://cve.tuxcare.com/els/releases/CLSA-2026:1777970333");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages based on the guidance in TuxCare advisory CENTOS7:CLSA-2026:1777970333.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:N/I:P/A:P");
  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:H/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:P/PR:L/UI:N/VC:L/VI:H/VA:N/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-2021-23336");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2022-37454");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-1299");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"vendor_severity", value:"Critical");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/01/28");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/05/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/01");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CentOS 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/OS/extended-third-party", "Host/local_checks_enabled", "Host/CentOS/release", "Host/CentOS/rpm-list");

  exit(0);
}
include('rpm2.inc');

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (empty_or_null(third_party_support) || third_party_support != 'TuxCare') exit(0, 'TuxCare support not enabled.');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || 'CentOS Linux' >!< os_product) audit(AUDIT_OS_NOT, 'CentOS Linux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'CentOS Linux');
if (! preg(pattern:"^7([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'CentOS Linux 7', 'CentOS Linux ' + os_version);

if (!get_kb_item('Host/CentOS/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if (cpu !~ "^i[3-6]86$" && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'CentOS Linux', cpu);


var constraints = [
  {
    'release': '7',
    'pkgs': [
      {'reference':'python3-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'i686', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'x86_64', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-debug-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'i686', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-debug-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'x86_64', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-devel-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'i686', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-devel-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'x86_64', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-idle-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'i686', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-idle-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'x86_64', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-libs-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'i686', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-libs-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'x86_64', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-test-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'i686', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-test-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'x86_64', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-tkinter-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'i686', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'python3-tkinter-3.6.8-21.0.5.el7_9.tuxcare.els8', 'cpu':'x86_64', 'el_string':'el7_9', 'rpm_spec_vers_cmp':TRUE}
    ]
  }
];

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
foreach var constraint ( constraints ) {
  # Check that the target release is equal to the affected release
  if (!empty_or_null(constraint['release'])){
    if (constraint['release'] != os_release) continue;
  }
  if (!empty_or_null(constraint['sp'])){
    if (constraint['sp'] != os_sp) continue;
  }
  foreach var pkg ( constraint['pkgs'] ) {
    reference = NULL;
    sp = NULL;
    _cpu = NULL;
    el_string = NULL;
    rpm_spec_vers_cmp = NULL;
    epoch = NULL;
    allowmaj = NULL;
    exists_check = NULL;
    cves = NULL;
    if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
    if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
    if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (reference &&
        ## (no known rpm to check OR known rpm_exists)
        (!exists_check || rpm_exists(rpm:exists_check)) &&
        rpm_check(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 / python3-debug / python3-devel / python3-idle / etc');
}