XSS in Keycloak
CVE-2025-10044
A flaw was found in Keycloak. Keycloak’s account console and other pages accept arbitrary text in the error_description query parameter. This text is directly rendered in error pages without validation or sanitization. While HTML encoding prevents XSS, an attacker can craft URLs with misleading messages (e.g., fake support phone numbers or URLs), which are displayed within the trusted Keycloak UI. This creates a phishing vector, potentially tricking users into contacting malicious actors.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (21.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: -0.000
Affected products
- Keycloak — versions 0
- Red Hat Build Of Keycloak 26.0 — versions 26.0.17-1, 26.0-21, 26.0-22
- Red Hat Build Of Keycloak 26.0.17
- Red Hat Build Of Keycloak 26.2 — versions 26.2.9-1, 26.2-9
- Red Hat Build Of Keycloak 26.2.9
Weakness classification (CWE)
References
- access.redhat.com/errata/RHSA-2025:16399 (vendor-advisory)
- access.redhat.com/errata/RHSA-2025:16400 (vendor-advisory)
- access.redhat.com/errata/RHSA-2025:19923 (vendor-advisory)
- access.redhat.com/errata/RHSA-2025:19925 (vendor-advisory)
- access.redhat.com/security/cve/CVE-2025-10044 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
- github.com/keycloak/keycloak/pull/42443
Frequently asked questions
- What is CVE-2025-10044?
- CVE-2025-10044 is a medium-severity vulnerability in Keycloak, classified under Cross-site Scripting. CVSS score: 4.3/10. Published 2025-09-05.
- How severe is CVE-2025-10044?
- Medium severity. CVSS v3 base score is 4.3 out of 10.