GHSA-f4cf-9rvr-2rcx
MEDIUMZitadel Discloses the Total Number of Instance Users
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
github.com/zitadel/zitadel🐹github.com/zitadel/zitadel🐹github.com/zitadel/zitadelReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Zitadel's User Service discloses the total number of instance users to unauthorized users.
Impact
The ZITADEL User Service exposes the total number of users within an instance to any authenticated user, regardless of their specific permissions. While this does not leak individual user data or PII, disclosing the total user count via the totalResult field constitutes an information disclosure vulnerability that may be sensitive in certain contexts.
Affected Versions
Systems running one of the following version are affected:
- 4.x:
4.0.0-rc.1through4.7.1 - 3.x:
3.0.0-rc.1through3.4.4 - 2.x:
2.44.0through2.71.19
Patches
The vulnerability has been addressed in the latest release. The patch resolves the issue and returns the totalResult value corresponding to the number of instance users for whom the querying user has read permission.
- 4.x: Upgrade to >= 4.7.2
- 3.x: Update to >= 3.4.5
- 2.x: Update to >= 3.4.5 (or checkout the workarounds section)
Workarounds
The recommended solution is to update Zitadel to a patched version.
If a version upgrade is not possible, you can enable the permissionCheckV2 feature on your instance.
Questions
If you have any questions or comments about this advisory, please email us at [email protected]
Credits
This vulnerability was found by zentrust partners GmbH during a scheduled penetration test. Thank you to the analysts Martin Tschirsich, Joud Zakharia, Christopher Baumann. The full report will be made public after the complete review.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/zitadel/zitadel | ≥ 4.0.0-rc.1&&< 4.7.2 | 4.7.2 |
| 🐹Go | github.com/zitadel/zitadel | ≥ 2.44.0&&< 3.4.5 | 3.4.5 |
| 🐹Go | github.com/zitadel/zitadel | all versions | 1.80.0-v2.20.0.20251210121356-826039c6208f |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/zitadel/zitadel. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/zitadel/zitadel to 4.7.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-f4cf-9rvr-2rcx is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-f4cf-9rvr-2rcx is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-f4cf-9rvr-2rcx. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-f4cf-9rvr-2rcx in your dependencies?
O3 detects GHSA-f4cf-9rvr-2rcx across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.