GHSA-9mvc-8737-8j8h
GHSA-9mvc-8737-8j8h is a CWE-770 vulnerability in pypdf. O3 Security confirms whether GHSA-9mvc-8737-8j8h is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
pypdf possibly has long runtimes for malformed FlateDecode streams
Blast Radius
pypdfReal-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
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a malformed /FlateDecode stream, where the byte-by-byte decompression is used.
Patches
This has been fixed in pypdf==6.7.1.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3644.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pypdf | all versions | 6.7.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pypdf. 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 pypdf to 6.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9mvc-8737-8j8h 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-9mvc-8737-8j8h 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-9mvc-8737-8j8h. 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-9mvc-8737-8j8h in your dependencies?
O3 detects GHSA-9mvc-8737-8j8h across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.