GHSA-77gc-fj98-665h
HIGHGHSA-77gc-fj98-665h is a high-severity (CVSS 7.5) CWE-284 vulnerability in gopkg.in/square/go-jose.v1. O3 Security confirms whether GHSA-77gc-fj98-665h is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Go JOSE Signature Validation Bypass
Blast Radius
gopkg.in/square/go-jose.v1Real-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
Go JOSE before 1.1.0 suffers from multiple signatures exploitation. The go-jose library supports messages with multiple signatures. However, when validating a signed message the API did not indicate which signature was valid, which could potentially lead to confusion. For example, users of the library might mistakenly read protected header values from an attached signature that was different from the one originally validated
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | gopkg.in/square/go-jose.v1 | all versions | 1.1.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for gopkg.in/square/go-jose.v1. 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 gopkg.in/square/go-jose.v1 to 1.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-77gc-fj98-665h 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-77gc-fj98-665h 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-77gc-fj98-665h. 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-77gc-fj98-665h in your dependencies?
O3 detects GHSA-77gc-fj98-665h across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.