CentOS Linux 6 [TuxCare] Security Update: spamassassin Multiple Vulnerabilities (CENTOS6:CLSA-2026:1777548877)

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

include('compat.inc');

if (description)
{
  script_id(359563);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/01");

  script_cve_id(
    "CVE-2017-15705",
    "CVE-2018-11781",
    "CVE-2018-11805",
    "CVE-2019-12420"
  );
  script_xref(name:"CLSA", value:"2026:1777548877");

  script_name(english:"CentOS Linux 6 [TuxCare] Security Update: spamassassin Multiple Vulnerabilities (CENTOS6:CLSA-2026:1777548877)");

  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 6 host has a package installed that is affected by multiple vulnerabilities as referenced in the
TuxCare CENTOS6:CLSA-2026:1777548877 advisory.

  - A denial of service vulnerability was identified that exists in Apache SpamAssassin before 3.4.2. The
    vulnerability arises with certain unclosed tags in emails that cause markup to be handled incorrectly
    leading to scan timeouts. In Apache SpamAssassin, using HTML::Parser, we setup an object and hook into the
    begin and end tag event handlers In both cases, the open event is immediately followed by a close
    event - even if the tag *does not* close in the HTML being parsed. Because of this, we are missing the
    text event to deal with the object normally. This can cause carefully crafted emails that might take
    more scan time than expected leading to a Denial of Service. The issue is possibly a bug or design
    decision in HTML::Parser that specifically impacts the way Apache SpamAssassin uses the module with poorly
    formed html. The exploit has been seen in the wild but not believed to have been purposefully part of a
    Denial of Service attempt. We are concerned that there may be attempts to abuse the vulnerability in the
    future. (CVE-2017-15705)

  - Apache SpamAssassin 3.4.2 fixes a local user code injection in the meta rule syntax. (CVE-2018-11781)

  - In Apache SpamAssassin before 3.4.3, nefarious CF files can be configured to run system commands without
    any output or errors. With this, exploits can be injected in a number of scenarios. In addition to
    upgrading to SA 3.4.3, we recommend that users should only use update channels or 3rd party .cf files from
    trusted places. (CVE-2018-11805)

  - In Apache SpamAssassin before 3.4.3, a message can be crafted in a way to use excessive resources.
    Upgrading to SA 3.4.3 as soon as possible is the recommended fix but details will not be shared publicly.
    (CVE-2019-12420)

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/centos6els/advisories/2026/clsa-2026_1777548877.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?9848e7f7");
  script_set_attribute(attribute:"see_also", value:"https://cve.tuxcare.com/els/releases/CLSA-2026:1777548877");
  script_set_attribute(attribute:"solution", value:
"Update the affected spamassassin package based on the guidance in TuxCare advisory CENTOS6:CLSA-2026:1777548877.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-11805");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2018-11781");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/09/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/30");
  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:"^6([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'CentOS Linux 6', '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': '6',
    'pkgs': [
      {'reference':'spamassassin-3.3.1-3.el6.tuxcare.els3', 'cpu':'x86_64', '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_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, 'spamassassin');
}