CentOS Linux 7 [TuxCare] Security Update: clamav / clamav-data / clamav-devel / clamav-doc / etc Multiple Vulnerabilities (CENTOS7:CLSA-2026:1787337364)

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

include('compat.inc');

if (description)
{
  script_id(361766);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/01");

  script_cve_id(
    "CVE-2026-20213",
    "CVE-2026-20214",
    "CVE-2026-20215",
    "CVE-2026-20216",
    "CVE-2026-20217"
  );
  script_xref(name:"CLSA", value:"2026:1787337364");

  script_name(english:"CentOS Linux 7 [TuxCare] Security Update: clamav / clamav-data / clamav-devel / clamav-doc / etc Multiple Vulnerabilities (CENTOS7:CLSA-2026:1787337364)");

  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-2026:1787337364 advisory.

  - A vulnerability in the PE file format parser of ClamAV could allow an unauthenticated, remote attacker to
    cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected
    device. This vulnerability is due to improper boundary checks for content in PE files during scanning,
    which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by
    submitting a crafted file that contains PE content to be scanned by ClamAV on an affected device. A
    successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting
    in a DoS condition on the affected software. (CVE-2026-20213)

  - A vulnerability in the FSG file format parser of ClamAV could allow an unauthenticated, remote attacker to
    cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected
    device. This vulnerability is due to improper boundary checks for content in FSG files during scanning,
    which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by
    submitting a crafted file that contains portable executable content compressed with FSG to be scanned by
    ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning
    process to terminate, resulting in a DoS condition on the affected software. (CVE-2026-20214)

  - A vulnerability in the 7z file format parser of ClamAV could allow an unauthenticated, remote attacker to
    cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected
    device. This vulnerability is due to improper boundary checks for content in 7z files during scanning,
    which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by
    submitting a crafted file that contains 7zcontent to be scanned by ClamAV on an affected device. A
    successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting
    in a DoS condition on the affected software. (CVE-2026-20215)

  - A vulnerability in the InstallShield file format parser of ClamAV could allow an unauthenticated, remote
    attacker to cause a DoS condition on an affected device. This vulnerability is due to improper handling of
    temporary resources during file scanning. An attacker could exploit this vulnerability by submitting a
    crafted InstallShield file to be scanned by ClamAV on an affected device. A successful exploit could allow
    the attacker to terminate the ClamAV scanning process and temporarily consume available system resources,
    resulting in a DoS condition on the affected software. (CVE-2026-20216)

  - A vulnerability in the PESpin file format parser of ClamAV could allow an unauthenticated, remote attacker
    to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an
    affected device. This vulnerability is due to improper boundary checks for content in PESpin files during
    scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability
    by submitting a crafted file that contains PESpin content to be scanned by ClamAV on an affected device. A
    successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting
    in a DoS condition on the affected software. (CVE-2026-20217)

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_1787337364.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?374bb5d7");
  script_set_attribute(attribute:"see_also", value:"https://cve.tuxcare.com/els/releases/CLSA-2026:1787337364");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages based on the guidance in TuxCare advisory CENTOS7:CLSA-2026:1787337364.");
  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:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-20217");

  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:"Important");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/07/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/21");
  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 ('x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'CentOS Linux', cpu);


var constraints = [
  {
    'release': '7',
    'pkgs': [
      {'reference':'clamav-1.4.3-1.el7.tuxcare.els2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamav-data-1.4.3-1.el7.tuxcare.els2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamav-devel-1.4.3-1.el7.tuxcare.els2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamav-doc-1.4.3-1.el7.tuxcare.els2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamav-filesystem-1.4.3-1.el7.tuxcare.els2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamav-freshclam-1.4.3-1.el7.tuxcare.els2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamav-lib-1.4.3-1.el7.tuxcare.els2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamav-milter-1.4.3-1.el7.tuxcare.els2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'clamd-1.4.3-1.el7.tuxcare.els2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'}
    ]
  }
];

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_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, 'clamav / clamav-data / clamav-devel / clamav-doc / etc');
}