Keycloak 26.7.3 <= 26.8.0 User Session Note Mapper Access Token Exposure (CVE-2026-105302)

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

include('compat.inc');

if (description)
{
  script_id(363812);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/07");

  script_cve_id("CVE-2026-105302");

  script_name(english:"Keycloak 26.7.3 <= 26.8.0 User Session Note Mapper Access Token Exposure (CVE-2026-105302)");

  script_set_attribute(attribute:"synopsis", value:
"An identity and access management application running on the remote host is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Keycloak installed on the remote host is 26.7.3 through 26.8.0. It is, therefore, affected by a
vulnerability where a User Session Note protocol mapper can expose upstream identity provider access tokens to
managed clients, allowing a client to obtain a token it was not intended to receive.

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://access.redhat.com/security/cve/CVE-2026-105302");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2545800");
  script_set_attribute(attribute:"see_also", value:"https://github.com/keycloak/keycloak/issues/53545");
  script_set_attribute(attribute:"see_also", value:"https://github.com/advisories/GHSA-3xph-hcf4-hx94");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory for patch or mitigation information.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:N/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-105302");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/10/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:keycloak:keycloak");
  script_set_attribute(attribute:"thorough_tests", value:"true");
  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("keycloak_nix_installed.nbin");
  script_require_keys("Host/local_checks_enabled", "Host/uname", "installed_sw/Keycloak");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'checks': [
    {
      'product': {'name': 'Keycloak', 'type': 'app'},
      'check_algorithm': 'default',
      'constraints': [
        {'min_version': '26.7.3', 'max_version': '26.8.0', 'fixed_display': 'See vendor advisory'}
      ]
    }
  ]
};

var res = vdf::check_and_report(vuln_data:vuln_data, severity:SECURITY_WARNING);
vdf::handle_check_and_report_errors(vdf_result:res);