XSS in Zitadel

CVE-2026-29191

ZITADEL is an open source identity management platform. From version 4.0.0 to 4.11.1, a vulnerability in Zitadel's login V2 interface was discovered that allowed a possible account takeover via XSS in /saml-post Endpoint. This issue has been patched in version 4.12.0.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (29.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.9% 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-2026-29191: held from 0.004 to 0.004.

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

Affected products

  • Zitadel — versions >= 4.0.0, < 4.12.0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-29191?
CVE-2026-29191 is a critical-severity vulnerability in Zitadel, classified under Cross-site Scripting. CVSS score: 9.3/10. Published 2026-03-07.
How severe is CVE-2026-29191?
Critical severity. CVSS v3 base score is 9.3 out of 10.