GHSA-h96w-mmrf-2h6v is a critical-severity (CVSS 9.8) CWE-444 vulnerability in twisted. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether GHSA-h96w-mmrf-2h6v is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Improper Input Validation in Twisted
Real-World Exposure
twistedReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
In Twisted Web before 20.3.0, there was an HTTP request splitting vulnerability. When presented with two content-length headers, it ignored the first header. When the second content-length value was set to zero, the request body was interpreted as a pipelined request.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | twisted | all versions | 20.3.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for twisted. 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 twisted to 20.3.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h96w-mmrf-2h6v 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-h96w-mmrf-2h6v 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-h96w-mmrf-2h6v. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
OpenShift Container Platform 4.3 and later includes `python-twisted` as a dependency of `python-prometheus_client` in Ironic container images, however the affected code is not used. Red Hat OpenStack Platform packages the flawed code, however python-twisted's web.HTTP functionality is not used in the RHOSP…
Frequently Asked Questions
Is GHSA-h96w-mmrf-2h6v in your dependencies?
O3 detects GHSA-h96w-mmrf-2h6v across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.