9.3

CVE-2026-109372: zitadel Improper Authentication

CVSS: 9.3v4.0CriticalDeferred
Published 12-10-2026Last modified 13-10-2026
Open JSON

Vulnerability summary

CVE-2026-109372 is a critical (CVSS 9.3) Improper Authentication vulnerability in zitadel. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 29.4% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.3/10
010
Critical · v4.0 (NVD)
EPSS score
0.37%
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. 13-10-2026
    Last modifiedVulnerability information updated.

Description

ZITADEL 4.x before 4.19.2 and 3.x through 3.4.15 contains an authentication bypass in the SAML identity-provider intent callback, which verifies the assertion signature using the provider named in the request URL but resolves the user from the login intent without checking they match. Attackers with organization-administrator permission can register a SAML provider with their own signing key to obtain authenticated sessions as any user linked to another SAML provider on the instance, including in other organizations.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.37%

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
0.37%

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

Zitadel1 product

1 vendor · 1 product

References

2 links