RHEL 8 : squid:4 (RHSA-2026:20564)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2026:20564. The text
# itself is copyright (C) Red Hat, Inc.
##

include('compat.inc');

if (description)
{
  script_id(316815);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/26");

  script_cve_id("CVE-2026-32748", "CVE-2026-33526");
  script_xref(name:"RHSA", value:"2026:20564");

  script_name(english:"RHEL 8 : squid:4 (RHSA-2026:20564)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat host is missing one or more security updates for squid:4.");
  script_set_attribute(attribute:"description", value:
"The remote Redhat Enterprise Linux 8 host has packages installed that are affected by multiple vulnerabilities as
referenced in the RHSA-2026:20564 advisory.

    Squid is a high-performance proxy caching server for web clients, supporting FTP, and HTTP data objects.

    Security Fix(es):

    * squid: Squid: Denial of Service via heap Use-After-Free vulnerability in ICP handling (CVE-2026-33526)

    * Squid: Squid: Denial of Service via crafted ICP traffic (CVE-2026-32748)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and
    other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux 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://access.redhat.com/security/updates/classification/#important");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2451574");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2451577");
  # https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_20564.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6bd58a25");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2026:20564");
  script_set_attribute(attribute:"solution", value:
"Update the RHEL squid:4 package based on the guidance in RHSA-2026:20564.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/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: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:H");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-33526");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(825, 826);
  script_set_attribute(attribute:"vendor_severity", value:"Important");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/03/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/05/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/05/26");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:8");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:rhel_aus:8.4");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libecap");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libecap-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:squid");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Red Hat 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", "redhat_repos.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");

  exit(0);
}


include('rpm2.inc');
include('rhel.inc');

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) || 'Red Hat' >!< os_product) audit(AUDIT_OS_NOT, 'Red Hat');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'Red Hat');
if (!rhel_check_release(operator: 'eq', os_version: os_version, rhel_version: '8.4')) audit(AUDIT_OS_NOT, 'Red Hat 8.4', 'Red Hat ' + os_version);

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

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu && 'ppc' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Red Hat', cpu);

var constraints = {
  'squid:4': [
    {
      'release': '8',
      'sp': '4',
      'repo_relative_urls': [
        'content/aus/rhel8/8.4/x86_64/appstream/debug',
        'content/aus/rhel8/8.4/x86_64/appstream/os',
        'content/aus/rhel8/8.4/x86_64/appstream/source/SRPMS',
        'content/extended-eus/rhel8/8.4/x86_64/appstream/debug',
        'content/extended-eus/rhel8/8.4/x86_64/appstream/os',
        'content/extended-eus/rhel8/8.4/x86_64/appstream/source/SRPMS'
      ],
      'pkgs': [
        {'reference':'libecap-1.0.1-2.module+el8.1.0', 'sp':'4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
        {'reference':'libecap-devel-1.0.1-2.module+el8.1.0', 'sp':'4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
        {'reference':'squid-4.11-4.module+el8.4.0', 'sp':'4', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE, 'epoch':'7'}
      ]
    }
  ]
};

var applicable_repo_urls = rhel_determine_applicable_repository_urls(constraints:constraints, appstreams:TRUE);
if(applicable_repo_urls == RHEL_REPOS_NO_OVERLAP_MESSAGE) exit(0, RHEL_REPO_NOT_ENABLED);

var module_ver = get_kb_item('Host/RedHat/appstream/squid');
if (isnull(module_ver)) audit(AUDIT_PACKAGE_NOT_INSTALLED, 'Module squid:4');
if ('4' >!< module_ver) audit(AUDIT_PACKAGE_NOT_AFFECTED, 'Module squid:' + module_ver);

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;
var repo_relative_urls;
var appstreams_found = 0;
var appstream;
var appstream_name;
var appstream_version;
foreach var module (keys(constraints)) {
  appstream = NULL;
  appstream_name = NULL;
  appstream_version = NULL;
  appstream_split = split(module, sep:':', keep:FALSE);
  if (!empty_or_null(appstream_split)) {
    appstream_name = appstream_split[0];
    appstream_version = appstream_split[1];
    if (!empty_or_null(appstream_name)) appstream = get_one_kb_item('Host/RedHat/appstream/' + appstream_name);
  }
  if (!empty_or_null(appstream) && appstream_version == appstream || appstream_name == 'all') {
    appstreams_found++;
    foreach var module_array ( constraints[module] ) {
      # Check that the target release is equal to the affected release
      if (!empty_or_null(module_array['release'])){
        if (module_array['release'] != os_release) continue;
      }
      if (!empty_or_null(module_array['sp'])){
        if (module_array['sp'] != os_sp) continue;
      }
      repo_relative_urls = NULL;
      if (!empty_or_null(module_array['repo_relative_urls'])) repo_relative_urls = module_array['repo_relative_urls'];
      foreach var package_array ( module_array['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(package_array['reference'])) reference = package_array['reference'];
        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 &&
            rhel_decide_repo_relative_url_check(required_repo_url_list:repo_relative_urls) &&
            (applicable_repo_urls || (!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 (!appstreams_found) audit(AUDIT_PACKAGE_NOT_INSTALLED, 'Module squid:4');

if (flag)
{
  var subscription_caveat = '\n' +
    'NOTE: This vulnerability check contains fixes that apply to\n' +
    'packages only available in the Red Hat Enterprise Linux\n' +
    'Advanced Update Support or Extended Update Support repositories.\n' +
    'Access to these repositories requires a paid RHEL subscription.\n';
  var extra = NULL;
  if (isnull(applicable_repo_urls) || !applicable_repo_urls) extra = subscription_caveat + rpm_report_get() + redhat_report_repo_caveat();
  else extra = subscription_caveat + rpm_report_get();
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : extra
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libecap / libecap-devel / squid');
}