CVE-2026-97174
MEDIUM
MEDIUM
Priority: 0.03
BB Relevance:
54/100
Published: 2026-11-05
Modified: 2026-11-06
First seen: 2026-11-05
Status: active
Attack Surface
Network
No Interaction
Conf. Impact
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
High
PR:
Low
UI:
None
S:
Unchanged
C:
High
I:
High
A:
None
Description
A flaw was found in the Client-Initiated Backchannel Authentication (CIBA) implementation of Keycloak. The CIBA endpoint fails to properly validate the sub parameter, allowing it to be stored as an additional request parameter. During the token issuance process, this injected value overwrites the legitimate subject identifier. This allows an attacker to authenticate as themselves but receive security tokens belonging to a different victim user, leading to unauthorized account access.
Weakness Classification (1)
References & Advisories (4)
vendor-advisory
x_refsource_REDHAT
vdb-entry
x_refsource_REDHAT
issue-tracking
x_refsource_REDHAT