What is CVE-2020-10748?

CVE-2020-10748 is a medium-severity vulnerability in Red Hat Keycloak, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2020-09-16.

How severe is CVE-2020-10748?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Red Hat Keycloak

CVE-2020-10748

A flaw was found in Keycloak's data filter, in version 10.0.1, where it allowed the processing of data URLs in some circumstances. This flaw allows an attacker to conduct cross-site scripting or further attacks.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2020-09-16 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.009 (59.2th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 59.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Red Hat Keycloak — versions 10.0.1
Red Hat Single Sign-On
Keycloak — versions keycloak 10.0.1

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

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

Frequently asked questions

What is CVE-2020-10748?: CVE-2020-10748 is a medium-severity vulnerability in Red Hat Keycloak, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2020-09-16.
How severe is CVE-2020-10748?: Medium severity. CVSS v3 base score is 6.1 out of 10.