GHSA-68xg-gqqm-vgj8
CRITICALPuma HTTP Request/Response Smuggling vulnerability
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
puma💎pumaReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Impact
Prior to version 6.3.1, puma exhibited incorrect behavior when parsing chunked transfer encoding bodies and zero-length Content-Length headers in a way that allowed HTTP request smuggling.
The following vulnerabilities are addressed by this advisory:
- Incorrect parsing of trailing fields in chunked transfer encoding bodies
- Parsing of blank/zero-length Content-Length headers
Patches
The vulnerability has been fixed in 6.3.1 and 5.6.7.
Workarounds
No known workarounds.
References
For more information
If you have any questions or comments about this advisory:
Open an issue in Puma See our security policy
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | puma | all versions | 5.6.7 |
| 💎RubyGems | puma | ≥ 6.0.0&&< 6.3.1 | 6.3.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for puma. 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 puma to 5.6.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-68xg-gqqm-vgj8 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-68xg-gqqm-vgj8 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-68xg-gqqm-vgj8. 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-68xg-gqqm-vgj8 in your dependencies?
O3 detects GHSA-68xg-gqqm-vgj8 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.