GHSA-6w4m-2xhg-2658
CRITICALBuffer overflow in sponge queue functions
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
pysha3💎sha3Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI, RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Impact
The Keccak sponge function interface accepts partial inputs to be absorbed and partial outputs to be squeezed. A buffer can overflow when partial data with some specific sizes are queued, where at least one of them has a length of 2^32 - 200 bytes or more.
Patches
Yes, see commit fdc6fef0.
Workarounds
The problem can be avoided by limiting the size of the partial input data (or partial output digest) below 2^32 - 200 bytes. Multiple calls to the queue system can be chained at a higher level to retain the original functionality. Alternatively, one can process the entire input (or produce the entire output) at once, avoiding the queuing functions altogether.
References
See issue #105 for more details.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pysha3 | all versions | No fix |
| 💎RubyGems | sha3 | all versions | 1.0.5 |
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 pysha3. 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
No patched version of pysha3 has shipped for GHSA-6w4m-2xhg-2658 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
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-6w4m-2xhg-2658 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-6w4m-2xhg-2658. 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-6w4m-2xhg-2658 in your dependencies?
O3 detects GHSA-6w4m-2xhg-2658 across PyPI, RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.