Linux Distros Unpatched Vulnerability : CVE-2026-114349

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

include('compat.inc');

if (description)
{
  script_id(373877);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/29");

  script_cve_id("CVE-2026-114349");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-114349");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - When a broker decodes a compressed record batch, the per-record decoder reads a declared body size from
    the decompressed stream and allocates a buffer of that size before validating it against the bytes
    available or any configured limit. The size is attacker-controlled, and the batch CRC does not constrain
    it, so a small (around 90-byte), CRC-valid compressed produce request can declare a body size of up to
    about 2 GiB and force the broker to attempt that allocation, raising OutOfMemoryError. The record size
    limit (max.message.bytes), the request size limit, and client/broker quotas bound only the compressed wire
    size, not the declared decompressed size. Impact: An authenticated principal with Write on a topic can
    crash broker request-handler threads (reached when a batch's codec differs from the topic's
    compression.type and records are re-encoded) and any consumer that fetches the record, denying service. On
    brokers started with -XX:+ExitOnOutOfMemoryError, a common hardening, a single crafted request terminates
    the broker JVM. More seriously, a crafted record is accepted at ingest and written to disk; when the log-
    cleaner later reads it on a compacted topic, the OutOfMemoryError (an Error, not an Exception) terminates
    the cleaner thread, which is not restarted. With the default of a single cleaner thread, log compaction
    then stops for the entire broker, including the internal __consumer_offsets and __transaction_state
    topics, and the condition persists across restarts until the offending record is removed. The impact is
    availability only; no data is disclosed or altered. Mitigation: Upgrade to Apache Kafka 4.2.2, 4.3.2, or
    4.4.0, and set max.decompressed.message.bytes (at the broker and/or topic level) to a bounded value
    appropriate for your workload. Upgrading alone is not sufficient: for backward compatibility this
    configuration defaults to an effectively unlimited value (about 2 GiB), so a broker remains exposed until
    the limit is set. Choose a value at or slightly above the largest legitimate decompressed record your
    applications produce, and comfortably below the broker heap divided by the number of request-handler and
    cleaner threads. Until you can upgrade and configure the limit, restrict Write access to trusted
    producers; quotas and max.message.bytes do not mitigate this issue. Resolution: From Apache Kafka 4.2.2,
    4.3.2, and 4.4.0: the broker validates a record's declared decompressed body size against
    max.decompressed.message.bytes before allocating, on the produce-validation, log-compaction, and
    timestamp-lookup paths, and rejects oversized or negative sizes with InvalidRecordException. Operators
    must set this configuration to a bounded value to be protected, as its default is effectively unlimited.
    (CVE-2026-114349)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-114349");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-114349");

  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_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/10/28");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/29");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:kafka");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  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", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/Ubuntu Linux-18.04");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/Debian/dpkg-l"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "kafka"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (!empty_or_null(third_party_support)) {
    var third_party_vendors = distro_constraints_values['third_party'];
    if (!empty_or_null(third_party_vendors)) {
        var vendor;
        foreach vendor (third_party_vendors) {
            if (vendor == third_party_support) exit(0, 'A third party management patch is available for this vulnerability from ' + vendor + '.\n');
        }
    }
}

var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}