What is CVE-2020-27826?

CVE-2020-27826 is a medium-severity vulnerability in Red Hat Keycloak, classified under CWE-250. CVSS score: 4.2/10. Published 2021-05-28.

How severe is CVE-2020-27826?

Medium severity. CVSS v3 base score is 4.2 out of 10.

Vulnerability in Red Hat Keycloak

CVE-2020-27826

A flaw was found in Keycloak before version 12.0.0 where it is possible to update the user's metadata attributes using Account REST API. This flaw allows an attacker to change its own NameID attribute to impersonate the admin user for any particular application.

Published 2021-05-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (45.2th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 45.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Red Hat Keycloak
Red Hat Single Sign-On — versions 7.4, 7.4.4
Keycloak — versions keycloak 12.0.0

Weakness classification (CWE)

CWE-250

References

bugzilla.redhat.com/show_bug.cgi (Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2020-27826?: CVE-2020-27826 is a medium-severity vulnerability in Red Hat Keycloak, classified under CWE-250. CVSS score: 4.2/10. Published 2021-05-28.
How severe is CVE-2020-27826?: Medium severity. CVSS v3 base score is 4.2 out of 10.