3.1
LOW CVSS 3.1
CVE-2026-4874
Org.keycloak.protocol.oidc.grants: org.keycloak.services.managers: keycloak: server-side request forgery via oidc token endpoint manipulation
Description

A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to information disclosure.

INFO

Published Date :

March 26, 2026, 8:16 a.m.

Last Modified :

March 26, 2026, 8:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-4874 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 LOW 53f830b8-0a3f-465b-8143-3b8a9948e749
CVSS 3.1 LOW [email protected]
Solution
Update Keycloak to fix SSRF vulnerability by validating the client_session_host parameter.
  • Update Keycloak to the latest version.
  • Validate the client_session_host parameter during token refresh.
  • Restrict usage of backchannel.logout.url placeholder.
  • Review client configurations for backchannel.logout.url.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-4874.

URL Resource
https://access.redhat.com/security/cve/CVE-2026-4874
https://bugzilla.redhat.com/show_bug.cgi?id=2451611
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-4874 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-4874 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-4874 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-4874 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Mar. 26, 2026

    Action Type Old Value New Value
    Added Description A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to information disclosure.
    Added CVSS V3.1 AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
    Added CWE CWE-918
    Added Reference https://access.redhat.com/security/cve/CVE-2026-4874
    Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2451611
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.