RockyLinux 8 : perl-YAML:1.24 (RLSA-2026:93471)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# Rocky Linux Security Advisory RLSA-2026:93471.
##

include('compat.inc');

if (description)
{
  script_id(375447);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/11/03");

  script_cve_id("CVE-2017-20285", "CVE-2019-25777");
  script_xref(name:"RLSA", value:"2026:93471");

  script_name(english:"RockyLinux 8 : perl-YAML:1.24 (RLSA-2026:93471)");

  script_set_attribute(attribute:"synopsis", value:
"The remote RockyLinux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote RockyLinux 8 host has a package installed that is affected by multiple vulnerabilities as referenced in the
RLSA-2026:93471 advisory.

    * perl-yaml: perl-yaml: Arbitrary code execution via unrestricted package variable assignment
    (CVE-2019-25777)

    * perl-yaml: perl-yaml: Arbitrary destructor method execution via crafted YAML document (CVE-2017-20285)

Tenable has extracted the preceding description block directly from the RockyLinux 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://errata.rockylinux.org/RLSA-2026:93471");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2545818");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2545820");
  script_set_attribute(attribute:"solution", value:
"Update the affected perl-YAML package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/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:N/S:U/C:H/I:H/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-2017-20285");

  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:"2026/10/05");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/11/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/11/03");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:rocky:linux:perl-YAML");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:rocky:linux:8");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Rocky 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_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RockyLinux/release", "Host/RockyLinux/rpm-list", "Host/cpu");

  exit(0);
}


include('rpm2.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) || 'Rocky Linux' >!< os_product) audit(AUDIT_OS_NOT, 'Rocky Linux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'Rocky Linux');
if (! preg(pattern:"^8([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'RockyLinux 8.x', 'Rocky Linux ' + os_version);

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

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

var module_ver = get_kb_item('Host/RockyLinux/appstream/perl-YAML');
if (isnull(module_ver)) audit(AUDIT_PACKAGE_NOT_INSTALLED, 'Module perl-YAML:1.24');
if ('1.24' >!< module_ver) audit(AUDIT_PACKAGE_NOT_AFFECTED, 'Module perl-YAML:' + module_ver);

var constraints = {
  'perl-YAML:1.24': [
    {
      'release': '8',
      'pkgs': [
        {'reference':'perl-YAML-1.24-4.module+el8.10.0', 'el_string':'el8.10.0', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
        {'reference':'perl-YAML-1.24-4.module+el8.10.0', 'el_string':'el8.10.0', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
        {'reference':'perl-YAML-1.24-4.module+el8.10.0', 'el_string':'el8.10.0', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
        {'reference':'perl-YAML-1.24-4.module+el8.10.0', 'el_string':'el8.10.0', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'}
      ]
    }
  ]
};

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 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/RockyLinux/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;
      }
      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 &&
            (!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 perl-YAML:1.24');
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, 'perl-YAML');
}