Splunk Universal Forwarder 9.3.0 < 9.3.11, 9.4.0 < 9.4.10, 10.0.0 < 10.0.4, 10.2.0 < 10.2.1 (SVD-2026-0404)

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

include('compat.inc');

if (description)
{
  script_id(306778);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/16");

  script_cve_id("CVE-2026-22796");

  script_name(english:"Splunk Universal Forwarder 9.3.0 < 9.3.11, 9.4.0 < 9.4.10, 10.0.0 < 10.0.4, 10.2.0 < 10.2.1 (SVD-2026-0404)");

  script_set_attribute(attribute:"synopsis", value:
"An application running on a remote web server host is affected by a vulnerability");
  script_set_attribute(attribute:"description", value:
"The version of Splunk installed on the remote host is prior to tested version. It is, therefore, affected by a
vulnerability as referenced in the SVD-2026-0404 advisory.

  - Issue summary: A type confusion vulnerability exists in the signature verification of signed PKCS#7 data
    where an ASN1_TYPE union member is accessed without first validating the type, causing an invalid or NULL
    pointer dereference when processing malformed PKCS#7 data. Impact summary: An application performing
    signature verification of PKCS#7 data or calling directly the PKCS7_digest_from_attributes() function can
    be caused to dereference an invalid or NULL pointer when reading, resulting in a Denial of Service. The
    function PKCS7_digest_from_attributes() accesses the message digest attribute value without validating its
    type. When the type is not V_ASN1_OCTET_STRING, this results in accessing invalid memory through the
    ASN1_TYPE union, causing a crash. Exploiting this vulnerability requires an attacker to provide a
    malformed signed PKCS#7 to an application that verifies it. The impact of the exploit is just a Denial of
    Service, the PKCS7 API is legacy and applications should be using the CMS API instead. For these reasons
    the issue was assessed as Low severity. The FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this
    issue, as the PKCS#7 parsing implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5,
    3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue. (CVE-2026-22796)

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://advisory.splunk.com/advisories/SVD-2026-0404.html");
  script_set_attribute(attribute:"solution", value:
"Upgrade Splunk Universal Forwarder to versions 10.2.1, 10.0.4, 9.4.10, 9.3.11, or higher.");
  script_set_attribute(attribute:"agent", value:"all");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/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:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-22796");

  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:"2024/04/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/16");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:splunk:splunk");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:splunk:universal_forwarder");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CGI abuses");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("splunkd_detect.nasl", "splunk_web_detect.nasl", "macos_splunk_installed.nbin", "splunk_win_installed.nbin", "splunk_nix_installed.nbin", "splunk_universal_forwarder_nix_installed.nbin", "splunk_universal_forwarder_win_installed.nbin");
  script_require_ports("installed_sw/Splunk", "installed_sw/Splunk Universal Forwarder");

  exit(0);
}

include('vcf.inc');
include('vcf_extras_splunk.inc');

var app_info = vcf::splunk::get_app_info();

var constraints = [
  { 'min_version' : '9.3.0', 'fixed_version' : '9.3.11', 'license' : 'Forwarder' },
  { 'min_version' : '9.4.0', 'fixed_version' : '9.4.10', 'license' : 'Forwarder' },
  { 'min_version' : '10.0.0', 'fixed_version' : '10.0.4', 'license' : 'Forwarder' },
  { 'min_version' : '10.2.0', 'fixed_version' : '10.2.1', 'license' : 'Forwarder' }
];
vcf::splunk::check_version_and_report(
    app_info:app_info,
    constraints:constraints,
    severity:SECURITY_WARNING
);