GHSA-35vc-w93w-75c2 is a medium-severity (CVSS 6.3) Open Redirect vulnerability in github.com/pomerium/pomerium. O3 Security confirms whether GHSA-35vc-w93w-75c2 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
JWT leak via Open Redirect in Programmatic access
Real-World Exposure
github.com/pomerium/pomeriumReal-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
Impact
Using programmatic access on protected sites, one can get a signed login URL with pomerium_redirect_uri set to an arbitrary URL. Then, if the user has already logged into Pomerium, they will be redirected to the specified pomerium_redirect_uri with a JWT attached. This allows an outside attacker to get a signed login URL that, upon visiting it, will redirect a victim to the attacker’s site. This creates an issue of Open Redirect and, more seriously, JWT leakage.
With a leaked JWT, the attacker will be able to unveil the victim’s identity (.e.g. email address) by supplying the JWT to the authenticate service or verify.pomerium.com. In addition, if an application integrating Pomerium only verifies the iss claim and others but not the aud claim, the attacker will be able to access it as the victim.
Specific Go Packages Affected
github.com/pomerium/pomerium/proxy
Patches
Patched in Pomerium v0.13.4
For more information
If you have any questions or comments about this advisory
- Open an issue in pomerium
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/pomerium/pomerium | all versions | 0.13.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/pomerium/pomerium. 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/pomerium/pomerium to 0.13.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-35vc-w93w-75c2 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-35vc-w93w-75c2 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-35vc-w93w-75c2. 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-35vc-w93w-75c2 in your dependencies?
O3 detects GHSA-35vc-w93w-75c2 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.