GHSA-c76h-2ccp-4975 is a medium-severity (CVSS 6.8) Insufficient Random Values vulnerability in undici. O3 Security confirms whether GHSA-c76h-2ccp-4975 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Use of Insufficiently Random Values in undici
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
undicinpmDescription
Impact
Undici fetch() uses Math.random() to choose the boundary for a multipart/form-data request. It is known that the output of Math.random() can be predicted if several of its generated values are known.
If there is a mechanism in an app that sends multipart requests to an attacker-controlled website, they can use this to leak the necessary values. Therefore, An attacker can tamper with the requests going to the backend APIs if certain conditions are met.
Patches
This is fixed in 5.28.5; 6.21.1; 7.2.3.
Workarounds
Do not issue multipart requests to attacker controlled servers.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | undici | ≥ 4.5.0&&< 5.28.5 | 5.28.5 |
| 📦npm | undici | ≥ 6.0.0&&< 6.21.1 | 6.21.1 |
| 📦npm | undici | ≥ 7.0.0&&< 7.2.3 | 7.2.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for undici. 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 undici to 5.28.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c76h-2ccp-4975 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-c76h-2ccp-4975 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-c76h-2ccp-4975. 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-c76h-2ccp-4975 in your dependencies?
O3 detects GHSA-c76h-2ccp-4975 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.