Medium severity · published Sep 24, 2026
CVE-2026-97176
Keycloak-services: keycloak-services: essential acr requirement silently bypassed via cookie authenticator
4.2
CVSS
0.2%
EPSS
No
On KEV
Description
A flaw was found in the Level of Authentication enforcement mechanism of Keycloak, an identity and access management solution. The issue occurs when a client specifically requires a higher security level for a user who already has an active session at a lower level. Due to a logic error in how session re-evaluations are handled, Keycloak may incorrectly issue a token at the lower security level instead of enforcing the required higher level, potentially allowing unauthorized access to sensitive resources that rely on these security claims.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat Build of Keycloak · Red Hat
All versions, or not specified · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-97176
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-97176
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-97176
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2539964
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