CVE-2026-15571

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.

CVSS v3 7.3 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.1 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:56523
https://access.redhat.com/errata/RHSA-2026:56524
https://access.redhat.com/security/cve/CVE-2026-15571
https://bugzilla.redhat.com/show_bug.cgi?id=2499591

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-18 21:16

Updated : 2026-08-20 15:17

NVD link : CVE-2026-15571

Mitre link : CVE-2026-15571

CVE.ORG link : CVE-2026-15571

JSON object : View

Products Affected

No product.

CWE

CWE-341

Predictable from Observable State

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