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

medium Nessus Plugin ID 363812

Synopsis

An identity and access management application running on the remote host is affected by a vulnerability.

Description

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.

Solution

Refer to the vendor advisory for patch or mitigation information.

Plugin Details

Severity: Medium

ID: 363812

File Name: keycloak_CVE-2026-105302.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 10/7/2026

Updated: 10/7/2026

Configuration: Enable thorough checks (optional)

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.68

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:N/A:N

CVSS Score Source: CVE-2026-105302

CVSS v3

Risk Factor: Medium

Base Score: 5.7

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N

Vulnerability Information

CPE: cpe:/a:keycloak:keycloak

Required KB Items: Host/local_checks_enabled, Host/uname, installed_sw/Keycloak

Vulnerability Publication Date: 10/2/2026

Reference Information

CVE: CVE-2026-105302

Detections

Analytics