TencentOS Server 3: ruby:3.3 (TSSA-2026:0933)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2026:0933.
##

include('compat.inc');

if (description)
{
  script_id(342068);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/01");

  script_cve_id(
    "CVE-2026-27820",
    "CVE-2026-42256",
    "CVE-2026-42257",
    "CVE-2026-47240",
    "CVE-2026-47241",
    "CVE-2026-47242"
  );
  script_xref(name:"IAVB", value:"2026-B-0117-S");
  script_xref(name:"IAVB", value:"2026-B-0162");

  script_name(english:"TencentOS Server 3: ruby:3.3 (TSSA-2026:0933)");

  script_set_attribute(attribute:"synopsis", value:
"The remote TencentOS Server 3 host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The version of Tencent Linux installed on the remote TencentOS Server 3 host is prior to tested version. It is,
therefore, affected by multiple vulnerabilities as referenced in the TSSA-2026:0933 advisory.

    Package updates are available for TencentOS Server 3 that fix the following vulnerabilities:

    CVE-2026-27820:
    zlib is a Ruby interface for the zlib compression/decompression library. Versions 3.0.0 and below, 3.1.0,
    3.1.1, 3.2.0 and 3.2.1 contain a buffer overflow vulnerability in the Zlib::GzipReader. The
    zstream_buffer_ungets function prepends caller-provided bytes ahead of previously produced output but
    fails to guarantee the backing Ruby string has enough capacity before the memmove shifts the existing
    data. This can lead to memory corruption when the buffer length exceeds capacity. This issue has been
    fixed in versions 3.0.1, 3.1.2 and 3.2.3.

    CVE-2026-42256:
    Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. From versions
    0.4.0 to before 0.4.24, 0.5.0 to before 0.5.14, and 0.6.0 to before 0.6.4, when authenticating a
    connection with SCRAM-SHA1 or SCRAM-SHA256, a hostile server can perform a computational denial-of-service
    attack on the client process by sending a big iteration count value. This issue has been patched in
    versions 0.4.24, 0.5.14, and 0.6.4.

    CVE-2026-42257:
    Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to
    versions 0.4.24, 0.5.14, and 0.6.4, several Net::IMAP commands accept a raw string argument that is sent
    to the server without validation or escaping. If this string is derived from user-controlled input, it may
    contain contain CRLF sequences, which an attacker can use to inject arbitrary IMAP commands. This issue
    has been patched in versions 0.4.24, 0.5.14, and 0.6.4.

    CVE-2026-47240:
    Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5
    and 0.5.15, several Net::IMAP commands accept a raw data argument that is sent verbatim after validation
    to prevent command injection. However, if a server does not support non-synchronizing literals, it may
    still be possible to inject arbitrary IMAP commands inside non-synchronizing literals.  A server without
    support for non-synchronizing literals may interpret the +}\r\n as the end of a malformed command line
    and respond with a tagged BAD. In that case, the contents of the literal will be interpreted as one or
    more new pipelined commands, allowing a CRLF command injection attack to succeed. This affects criteria
    for #search and #uid_search; search_keys for #sort, #thread, #uid_sort, and #uid_thread; and attr for
    #fetch and #uid_fetch. This vulnerability is fixed in 0.6.5 and 0.5.15.

    CVE-2026-47241:
    Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5
    and 0.5.15, several Net::IMAP commands accept a raw string argument which is only validated to prevent
    CRLF injection and then sent verbatim. If this string is derived from user-controlled input, an attacker
    can force the next command to be absorbed as a continuation of the first command. This will cause the
    first command to eventually fail, but also prevents it from returning until another command is sent (from
    another thread). That other command will not return until the connection is closed. This vulnerability is
    fixed in 0.6.5 and 0.5.15.

    CVE-2026-47242:
    Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5
    and 0.5.15, when Net::IMAP#id is called with a hash argument, although the ID field value strings are
    correctly quoted (escaping quoted specials), they were not validated to prohibit CRLF sequences. While
    Net::IMAP#enable does process its arguments for aliases, it does not validate them as valid atoms (or as a
    list of valid atoms). The #to_s value is sent verbatim. Arguments to either command could be used by an
    attacker to inject arbitrary IMAP commands. This vulnerability is fixed in 0.6.5 and 0.5.15.

Tenable has extracted the preceding description block directly from the Tencent 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://mirrors.tencent.com/tlinux/errata/tssa-20260933.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/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:N/AC:L/PR:N/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:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-42257");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-27820");

  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:"2026/04/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/01");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:tencent:tencentos_server:3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:tencent:tencentos_server:ruby");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:tencent:tencentos_server:rubygem-abrt");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:tencent:tencentos_server:rubygem-mysql2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:tencent:tencentos_server:rubygem-pg");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Tencent 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/etc/os-release", "Host/TencentOS/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) || 'TencentOS' >!< os_product) audit(AUDIT_OS_NOT, 'TencentOS');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'TencentOS');
if (! preg(pattern:"^3([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'TencentOS 3.x', 'TencentOS ' + os_version);

if (!get_kb_item('Host/TencentOS/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) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'TencentOS', cpu);

var constraints = [
  {
    'release': '3',
    'pkgs': [
      {'reference':'ruby-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-bundled-gems-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-bundled-gems-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-bundled-gems-debuginfo-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-bundled-gems-debuginfo-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-debuginfo-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-debuginfo-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-debugsource-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-debugsource-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-default-gems-3.3.12-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-devel-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-devel-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-doc-3.3.12-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-libs-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-libs-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-libs-debuginfo-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'ruby-libs-debuginfo-3.3.12-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-abrt-0.4.0-1.module+el8.10.0+741+a1723c19', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-abrt-doc-0.4.0-1.module+el8.10.0+741+a1723c19', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-bigdecimal-3.1.5-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-bigdecimal-3.1.5-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-bigdecimal-debuginfo-3.1.5-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-bigdecimal-debuginfo-3.1.5-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-bundler-2.5.22-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-io-console-0.7.1-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-io-console-0.7.1-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-io-console-debuginfo-0.7.1-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-io-console-debuginfo-0.7.1-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-irb-1.13.1-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-json-2.7.2-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-json-2.7.2-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-json-debuginfo-2.7.2-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-json-debuginfo-2.7.2-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-minitest-5.20.0-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-mysql2-0.5.5-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-mysql2-0.5.5-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-mysql2-debuginfo-0.5.5-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-mysql2-debuginfo-0.5.5-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-mysql2-debugsource-0.5.5-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-mysql2-debugsource-0.5.5-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-mysql2-doc-0.5.5-1.module+el8.10.0+809+e8c4dcf5', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-pg-1.5.4-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-pg-1.5.4-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-pg-debuginfo-1.5.4-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-pg-debuginfo-1.5.4-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-pg-debugsource-1.5.4-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-pg-debugsource-1.5.4-1.module+el8.10.0+809+e8c4dcf5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-pg-doc-1.5.4-1.module+el8.10.0+809+e8c4dcf5', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-power_assert-2.0.3-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-psych-5.1.2-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-psych-5.1.2-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-psych-debuginfo-5.1.2-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-psych-debuginfo-5.1.2-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-racc-1.7.3-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-racc-1.7.3-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-racc-debuginfo-1.7.3-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-racc-debuginfo-1.7.3-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rake-13.1.0-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rbs-3.4.0-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rbs-3.4.0-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rbs-debuginfo-3.4.0-8.module+el8.10.0+949+63f084dc', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rbs-debuginfo-3.4.0-8.module+el8.10.0+949+63f084dc', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rdoc-6.6.3.1-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rexml-3.4.4-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-rss-0.3.1-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-test-unit-3.6.1-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygem-typeprof-0.21.9-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygems-3.5.22-8.module+el8.10.0+949+63f084dc', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'rubygems-devel-3.5.22-8.module+el8.10.0+949+63f084dc', '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, 'ruby / ruby-bundled-gems / ruby-bundled-gems-debuginfo / etc');
}