Mattermost Server 10.11.x <= 10.11.9 / 11.1.x <= 11.1.2 / 11.2.x <= 11.2.1 Improper Access Control (MMSA-2025-00550)

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

include('compat.inc');

if (description)
{
  script_id(299395);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/30");

  script_cve_id("CVE-2026-22892");
  script_xref(name:"IAVA", value:"2026-A-0167-S");

  script_name(english:"Mattermost Server 10.11.x <= 10.11.9 / 11.1.x <= 11.1.2 / 11.2.x <= 11.2.1 Improper Access Control (MMSA-2025-00550)");

  script_set_attribute(attribute:"synopsis", value:
"The remote host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of Mattermost Server installed on the remote host is affected by a vulnerability as referenced in the
MMSA-2025-00550 advisory.

  - Mattermost versions 10.11.x <= 10.11.9, 11.1.x <= 11.1.2, and 11.2.x <= 11.2.1 fail to properly
    validate channel permissions when using the Jira plugin. This allows an authenticated user to access
    attachments and content from posts in channels they don't have permission to view by creating a Jira
    issue with an inaccessible post ID. (CVE-2026-22892)

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://mattermost.com/security-updates/");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Mattermost Server version 10.11.10, 11.1.3, 11.2.2, 11.3.0 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N");
  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:L/UI:N/S:U/C:L/I:N/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-2026-22892");

  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:"2026/01/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/01/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/02/18");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:mattermost:mattermost_server");
  script_set_attribute(attribute:"stig_severity", value:"I");
  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("mattermost_server_detect.nbin");
  script_require_keys("installed_sw/Mattermost Server");

  exit(0);
}

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

var port = get_http_port(default:80);

var app_info = vcf::get_app_info(app:'Mattermost Server', port:port, webapp:true);

var constraints = [
  { 'min_version' : '10.11.0', 'fixed_version' : '10.11.10' },
  { 'min_version' : '11.1.0', 'fixed_version' : '11.1.3' },
  { 'min_version' : '11.2.0', 'fixed_version' : '11.2.2', 'fixed_display' : '11.2.2 / 11.3.0' }
];

vcf::check_version_and_report(
    app_info:app_info,
    constraints:constraints,
    severity:SECURITY_WARNING
);