5.3

CVE-2026-23511: zitadel Observable Response Discrepancy

CVSS: 5.3v3.1MediumAnalyzed
AliasesGHSA-pvm5-9frx-264rGO-2026-4319
Published 15-01-2026Last modified 15-01-2026
Open JSON

Vulnerability summary

CVE-2026-23511 is a medium (CVSS 5.3) Observable Response Discrepancy vulnerability in zitadel. EPSS estimates a 0.40% chance of exploitation in the next 30 days, higher than 33.2% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.40%
0%100%
Low · -0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2 · Related 2
OPENSUSE-SU-2026:21483-1SUSE-SU-2026:0292-1

Timeline

  1. 15-01-2026
    PublishedVulnerability first disclosed.
  2. 15-01-2026
    Last modifiedVulnerability information updated.

Description

ZITADEL is an open source identity management platform. Prior to 4.9.1 and 3.4.6, a user enumeration vulnerability has been discovered in Zitadel's login interfaces. An unauthenticated attacker can exploit this flaw to confirm the existence of valid user accounts by iterating through usernames and userIDs. This vulnerability is fixed in 4.9.1 and 3.4.6.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.40%

Chance of exploitation in the next 30 days

Percentile

33%

Versus all other CVEs

30-day change

-0.01 pp

From 0.41% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.40%

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

Github.com/zitadel1 product
  • zitadel≥ 4.0.0, < 4.9.1 | < 3.4.6 | All versions (No fix recorded)
Zitadel1 product
  • zitadel< 3.4.6 | ≥ 2.0.0, ≤ 2.71.19 | ≥ 3.0.0, < 3.4.6 | ≥ 4.0.0, < 4.9.1

2 vendors · 2 products

References

8 links