XSS in Keycloak

CVE-2017-12158

It was found that Keycloak would accept a HOST header URL in the admin console and use it to determine web resource locations. An attacker could use this flaw against an authenticated user to attain reflected XSS via a malicious server.

Vulnerability class: HTTP Request Smuggling

EPSS: 0.010 (59.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2017-12158?
CVE-2017-12158 is a medium-severity vulnerability in Keycloak, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 5.4/10. Published 2017-10-26.
How severe is CVE-2017-12158?
Medium severity. CVSS v3 base score is 5.4 out of 10.