SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-4636

An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation.

HIGH 8.1EPSS 0.35%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.35%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A flaw was found in Keycloak. An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation. This allows the attacker to include resource identifiers owned by other users in a policy creation request, even if the URL path specifies an attacker-owned resource. Consequently, the attacker gains unauthorized permissions to victim-owned resources, enabling them to obtain a Requesting Party Token (RPT) and access sensitive information or perform unauthorized actions.

CVSS 3.1
8.1 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS
0.35% probability · 28th percentile
CISA KEV
Not listed
Weakness
CWE-551
Affected
redhat/build of keycloak
Source
secalert@redhat.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.