Vulnerability in Red Hat Build Of Keycloak

CVE-2026-88770

A flaw was found in the Device Authorization Grant flow of Keycloak, an identity and access management solution. The issue occurs because the token redemption process fails to check if a user account is currently locked due to brute-force protection. If an attacker has an active session for a locked account, they can complete the device login process and receive new security tokens. This allows the attacker to maintain access to the account even when it should be temporarily disabled to prevent unauthorized entry.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (27.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 27.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-88770: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-88770?
CVE-2026-88770 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Improper Restriction of Excessive Authentication Attempts. CVSS score: 6.5/10. Published 2026-09-10.
How severe is CVE-2026-88770?
Medium severity. CVSS v3 base score is 6.5 out of 10.