8.8

CVE-2026-109371: zitadel

CVSS: 8.8v4.0HighDeferred
AliasesCGA-6f62-fp64-xp34CGA-mrcq-wf7w-p4r4
Published 12-10-2026Last modified 15-10-2026
Open JSON

Vulnerability summary

CVE-2026-109371 is a high (CVSS 8.8) vulnerability in zitadel. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 28.7% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v4.0 (NVD)
EPSS score
0.36%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 12-10-2026
    PublishedVulnerability first disclosed.
  2. 15-10-2026
    Last modifiedVulnerability information updated.

Description

ZITADEL 3.0.0 before 4.18.0 contains a missing authentication vulnerability in the hosted Login V1 UI, where the change-username handler acts on the account bound to a login flow before any factor is verified. Unauthenticated attackers can submit a victim's login name and then post a new username to rename any active human user, including administrators, locking them out.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.36%

Chance of exploitation in the next 30 days

Percentile

29%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

13-10-202619-10-2026
EPSS score
0.36%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard1 product
  • zitadel-3All versions (No fix recorded)
Zitadel1 product

2 vendors · 2 products

References

2 links