CVE WatchJul 15, 2026

CVE-2026-4634

A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with an

CVSS

7.5

High

EPSS

0.5%

p41

KEV

—

Exploit Today

0-100

Published: Apr 2, 2026 · Last modified: Jul 15, 2026 · CWE-1050

EPSS · 30d

0.5%EPSS · 30 days0.5%

2026-06-302026-07-16

Technical description

A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with an excessively long scope parameter to the OpenID Connect (OIDC) token endpoint. This leads to high resource consumption and prolonged processing times, ultimately resulting in a Denial of Service (DoS) for the Keycloak server.

Official references

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