How severe is GHSA-v959-qxv6-6f8p?

GHSA-v959-qxv6-6f8p has a CVSS score of 8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-v959-qxv6-6f8p?

GHSA-v959-qxv6-6f8p affects the following packages: github.com/zitadel/zitadel (Go), github.com/zitadel/zitadel (Go), github.com/zitadel/zitadel (Go), github.com/zitadel/zitadel/v2 (Go). Ecosystems affected: Go.

How do I fix GHSA-v959-qxv6-6f8p?

Update github.com/zitadel/zitadel to 1.80.0-v2.20.0.20251208091519-4c879b47334e or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v959-qxv6-6f8p is resolved across your whole dependency graph.

How do I detect GHSA-v959-qxv6-6f8p in my Go dependencies?

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.

How do I mitigate GHSA-v959-qxv6-6f8p if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-v959-qxv6-6f8p?

O3 pinpoints whether GHSA-v959-qxv6-6f8p is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-v959-qxv6-6f8p actively exploited in the wild?

No public exploit code has been indexed for GHSA-v959-qxv6-6f8p yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-v959-qxv6-6f8p?

GHSA-v959-qxv6-6f8p has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 17th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-v959-qxv6-6f8p?

GHSA-v959-qxv6-6f8p is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-v959-qxv6-6f8p published, and has it been updated?

GHSA-v959-qxv6-6f8p was published on December 8, 2025 and was last updated on December 15, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

GHSA-v959-qxv6-6f8p

HIGH

ZITADEL Vulnerable to Account Takeover via DOM-Based XSS in Zitadel V2 Login

Also known asCVE-2025-67495GO-2025-4213

Published

Dec 8, 2025

Updated

Dec 15, 2025

Affected

4 pkgs

Patched

3 / 4

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk17th percentile+0.22%

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

4 pkgs affected

🐹github.com/zitadel/zitadel🐹github.com/zitadel/zitadel🐹github.com/zitadel/zitadel🐹github.com/zitadel/zitadel/v2

Real-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

A potential vulnerability exists in ZITADEL's logout endpoint in login V2. This endpoint accepts serval parameters including a post_logout_redirect. When this parameter is specified, users will be redirected to the site that is provided via this parameter. ZITADEL's login UI did not ensure that this parameter contained an allowed value and even executed passed scripts.

Impact

Zitadel is vulnerable to a DOM-Based XSS vulnerability. More specifically, the /logout endpoint insecurely routed to value that is supplied in the post_logout_redirect GET parameter. As a result, malicious JS code could be executed on Zitadel users’ browsers, in the Zitadel V2 Login domain.

An unauthenticated remote attacker can exploit this DOM-based XSS vulnerability, and thus, execute malicious JavaScript code on behalf of Zitadel users. By doing so, such an attacker could reset the password of their victims, and take over their accounts.

Note that for this to work, multiple user sessions need to be active in the same browser. Additionally, it's important to note that an account takeover is mitigated for accounts that have Multi-Factor Authentication (MFA) or Passwordless authentication enabled.

Affected Versions

Systems using the login UI (v2) and running one of the following versions are affected:

v4.x: 4.0.0-rc.1 through 4.7.0

Patches

The vulnerability has been addressed in the latest release. The patch resolves the issue by ensuring the information was passed for the ZITADEL API using a JSON Web Token (JWT). If you're running your own login UI, we recommend switching over to the new logout_token parameter, which contains all information previously passed via specific query parameters. The contained JWT's signature needs to be verified with the instance OAuth2/OIDC public keys (jwks_uri).

Before you upgrade, ensure that:

the ZITADEL_API_URL is set and is pointing to your instance, resp. system in multi-instance deployments.
the HTTP host (or a x-forwarded-host) is passed in your reverse proxy to the login UI.
a x-zitadel-instance-host (or x-zitadel-forward-host) is set in your reverse for multi-instance deployments. If you're running a single instance solution, you don't need to take any actions.

Patched versions:

4.x: Upgrade to >=4.7.1

Workarounds

The recommended solution is to update ZITADEL to a patched version.

Questions

If you have any questions or comments about this advisory, please email us at [email protected]

Credits

Thanks to Amit Laish – GE Vernova for finding and reporting the vulnerability.

Affected Packages

4 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/zitadel/zitadel`	all versions	1.80.0-v2.20.0.20251208091519-4c879b47334e
🐹Go	`github.com/zitadel/zitadel`	≥ 1.83.4	No fix
🐹Go	`github.com/zitadel/zitadel`	≥ 4.0.0-rc.1&&< 4.7.1	4.7.1
🐹Go	`github.com/zitadel/zitadel/v2`	all versions	1.80.0-v2.20.0.20251208091519-4c879b47334e

Detection & mitigation playbook

Open-source dependency

Detect
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 1.80.0-v2.20.0.20251208091519-4c879b47334e or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v959-qxv6-6f8p 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-v959-qxv6-6f8p 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-v959-qxv6-6f8p. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary A potential vulnerability exists in ZITADEL's logout endpoint in login V2. This endpoint accepts serval parameters including a `post_logout_redirect`. When this parameter is specified, users will be redirected to the site that is provided via this parameter. ZITADEL's login UI did not ensure that this parameter contained an allowed value and even executed passed scripts. ### Impact Zitadel is vulnerable to a DOM-Based XSS vulnerability. More specifically, the /logout endpoint insecurely routed to value that is supplied in the post_logout_redirect GET parameter. As a result, mali

O3 Security · Impact-Aware SCA

Is GHSA-v959-qxv6-6f8p in your dependencies?

O3 detects GHSA-v959-qxv6-6f8p across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

GHSA-v959-qxv6-6f8p

EPSS Exploitation Probability

Blast Radius

Description

Summary

Impact

Affected Versions

Patches

Workarounds

Questions

Credits

Affected Packages

Detection & mitigation playbook

Detect

Fix

Workarounds

How O3 protects you

Frequently Asked Questions

Is GHSA-v959-qxv6-6f8p in your dependencies?