CVE-2026-15571

Summary

A flaw was found in the legacy client-initiated account-linking endpoint of Keycloak, a widely used open-source identity and access management solution. The mechanism used to protect the account-linking process from unauthorized requests relies on a hash that can be predicted by a malicious OIDC client. By tricking a user into authenticating, an attacker-controlled client can forge a valid linking URL to connect the victim's account to an attacker's external identity. This results in a full account takeover, allowing the attacker to log in as the victim.

Affected Software

VendorProductVersion RangeStatus
Red HatRed Hat build of Keycloak 26.626.6-12 < *unaffected
Red HatRed Hat build of Keycloak 26.626.6.6-1 < *unaffected
Red HatRed Hat build of Keycloak 26.626.6-12 < *unaffected

Weaknesses

  • CWE-341: Predictable from Observable State

References