TencentOS Server 3: redis:6 (TSSA-2025:0449)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Tencent Linux Security Advisory TSSA-2025:0449.
##

include('compat.inc');

if (description)
{
  script_id(275960);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/12/04");

  script_cve_id("CVE-2025-21605");

  script_name(english:"TencentOS Server 3: redis:6 (TSSA-2025:0449)");

  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 a vulnerability as referenced in the TSSA-2025:0449 advisory.

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

    CVE-2025-21605:
    Redis is an open source, in-memory database that persists on disk. In versions starting at 2.6 and prior
    to 7.4.3, An unauthenticated client can cause unlimited growth of output buffers, until the server runs
    out of memory or is killed. By default, the Redis configuration does not limit the output buffer of normal
    clients (see client-output-buffer-limit). Therefore, the output buffer can grow unlimitedly over time. As
    a result, the service is exhausted and the memory is unavailable. When password authentication is enabled
    on the Redis server, but no password is provided, the client can still cause the output buffer to grow
    from NOAUTH responses until the system will run out of memory. This issue has been patched in version
    7.4.3. An additional workaround to mitigate this problem without patching the redis-server executable is
    to block access to prevent unauthenticated users from connecting to Redis. This can be done in different
    ways. Either using network access control tools like firewalls, iptables, security groups, etc, or
    enabling TLS and requiring users to authenticate using client side certificates.

Tenable has extracted the preceding description block directly from the Tencent Linux security advisory.

Note that Nessus has not tested for this issue 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-20250449.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  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:U/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:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-21605");

  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:"2025/04/23");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/05/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/11/20");

  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:redis");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Tencent Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2025 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':'redis-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-debuginfo-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-debuginfo-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-debugsource-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-debugsource-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-devel-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-devel-6.2.18-1.module+el8.10.0+746+668c92f5', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'redis-doc-6.2.18-1.module+el8.10.0+746+668c92f5', '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, 'redis / redis-debuginfo / redis-debugsource / etc');
}