TencentOS Server 3: go-toolset:rhel8 (TSSA-2026:0888)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2026:0888.
##

include('compat.inc');

if (description)
{
  script_id(341130);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/27");

  script_cve_id(
    "CVE-2026-33811",
    "CVE-2026-33814",
    "CVE-2026-39817",
    "CVE-2026-39819",
    "CVE-2026-39820",
    "CVE-2026-39823",
    "CVE-2026-39825",
    "CVE-2026-39826",
    "CVE-2026-39836",
    "CVE-2026-42499",
    "CVE-2026-42501"
  );
  script_xref(name:"IAVB", value:"2026-B-0120");

  script_name(english:"TencentOS Server 3: go-toolset:rhel8 (TSSA-2026:0888)");

  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-2026:0888 advisory.

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

    CVE-2026-33811:
    When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of
    C memory and a crash.

    CVE-2026-33814:
    When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION
    frames if it receives a SETTINGS_MAX_FRAME_SIZE with a value of 0.

    CVE-2026-39817:
    The go tool pack subcommand (usually used only by the compiler as an internal tool with known-good
    inputs) does not sanitize output filenames. Extracting a malicious archive file with the pack subcommand
    can write files to arbitrary locations on the filesystem.

    CVE-2026-39819:
    The go bug command writes to two files with predictable names in the system temporary directory (for
    example, /tmp). An attacker with access to the temporary directory can create a symlink in one of these
    names, causing go bug to overwrite the target of the symlink.

    CVE-2026-39820:
    Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive
    CPU exhaustion and memory allocations.

    CVE-2026-39823:
    CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a <meta> tag's
    <content> attribute. If the URL content were to insert ASCII whitespaces around the '=' rune inside of the
    <content> attribute, the escaper would fail to similarly escape it, leading to XSS.

    CVE-2026-39825:
    ReverseProxy can forward queries containing parameters not visible to Rewrite functions. When used with a
    Rewrite function, or a Director function which parses query parameters, ReverseProxy sanitizes the
    forwarded request to remove query parameters which are not parsed by url.ParseQuery. ReverseProxy does not
    take ParseQuery's limit on the total number of query parameters (controlled by
    GODEBUG=urlmaxqueryparams=N) into account. This can permit ReverseProxy to forward a request containing a
    query parameter that is not visible to the Rewrite function. For example, the query
    a1=x&a2=x&...&a10000=x&hidden=y can forward the parameter hidden=y while hiding it from the proxy's
    Rewrite function.

    CVE-2026-39826:
    If a trusted template author were to write a <script> tag containing an empty 'type' attribute or a 'type'
    attribute with an ASCII whitespace, the execution of the template would incorrectly escape any data passed
    into the <script> block.

    CVE-2026-39836:
    The Dial and LookupPort functions panic on Windows when provided with an input containing a NUL (0).

    CVE-2026-42499:
    Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC
    5322.

    CVE-2026-42501:
    A malicious module proxy can exploit a flaw in the go command's validation of module checksums to bypass
    checksum database validation. This vulnerability affects any user using an untrusted module proxy
    (GOMODPROXY) or checksum database (GOSUMDB). A malicious module proxy can serve altered versions of the Go
    toolchain. When selecting a different version of the Go toolchain than the currently installed toolchain
    (due to the GOTOOLCHAIN environment variable, or a go.work or go.mod with a toolchain line), the go
    command will download and execute a toolchain provided by the module proxy. A malicious module proxy can
    bypass checksum database validation for this downloaded toolchain. Since this vulnerability affects the
    security of toolchain downloads, setting GOTOOLCHAIN to a fixed version is not sufficient. You must
    upgrade your base Go toolchain. The go tool always validates the hash of a toolchain before executing it,
    so fixed versions will refuse to execute any cached, altered versions of the toolchain. The go tool trusts
    go.sum files to contain accurate hashes of the current module's dependencies. A malicious proxy exploiting
    this vulnerability to serve an altered module will have caused an incorrect hash to be recorded in the
    go.sum. Users who have configured a non-trusted GOPROXY can determine if they have been affected by
    running rm go.sum ; go mod tidy ; go mod verify, which will revalidate all dependencies of the current
    module. The specific flaw in more detail: The go command consults the checksum database to validate
    downloaded modules, when a module is not listed in the go.sum file. It verifies that the module hash
    reported by the checksum database matches the hash of the downloaded module. If, however, the checksum
    database returns a successful response that contains no entry for the module, the go command incorrectly
    permitted validation to succeed. A module proxy may mirror or proxy the checksum database, in which case
    the go command will not connect to the checksum database directly. Checksums reported by the checksum
    database are cryptographically signed, so a malicious proxy cannot alter the reported checksum for a
    module. However, a proxy which returns an empty checksum response, or a checksum response for an unrelated
    module, could cause the go command to proceed as if a downloaded module has been validated.

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-20260888.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:N/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:L/AC:L/PR:L/UI:R/S:C/C:N/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-2026-39817");

  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:"2026/05/07");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/27");

  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:delve");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:tencent:tencentos_server:golang");
  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':'delve-1.25.2-1.module+el8.10.0+805+5ec70a2a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'delve-1.25.2-1.module+el8.10.0+805+5ec70a2a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'delve-debuginfo-1.25.2-1.module+el8.10.0+805+5ec70a2a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'delve-debuginfo-1.25.2-1.module+el8.10.0+805+5ec70a2a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'delve-debugsource-1.25.2-1.module+el8.10.0+805+5ec70a2a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'delve-debugsource-1.25.2-1.module+el8.10.0+805+5ec70a2a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'go-toolset-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'go-toolset-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-bin-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-bin-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-docs-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-misc-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-race-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-race-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-src-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'golang-tests-1.25.10-1.module+el8.10.0+900+aca51a8a.ap.1', '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_WARNING,
      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, 'delve / delve-debuginfo / delve-debugsource / etc');
}