GHSA-v5m7-53cv-f3hx
HIGHcrossbeam-channel Undefined Behavior before v0.4.4
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
crossbeam-channelReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Impact
The affected version of this crate's the bounded channel incorrectly assumes that Vec::from_iter has allocated capacity that same as the number of iterator elements. Vec::from_iter does not actually guarantee that and may allocate extra memory. The destructor of the bounded channel reconstructs Vec from the raw pointer based on the incorrect assumes described above. This is unsound and causing deallocation with the incorrect capacity when Vec::from_iter has allocated different sizes with the number of iterator elements.
Patches
This has been fixed in crossbeam-channel 0.4.4.
We recommend users to upgrade to 0.4.4.
References
See https://github.com/crossbeam-rs/crossbeam/pull/533, https://github.com/crossbeam-rs/crossbeam/issues/539, and https://github.com/RustSec/advisory-db/pull/425 for more details.
License
This advisory is in the public domain.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | crossbeam-channel | ≥ 0.4.3&&< 0.4.4 | 0.4.4 |
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 crossbeam-channel. 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 crossbeam-channel to 0.4.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v5m7-53cv-f3hx 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-v5m7-53cv-f3hx 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-v5m7-53cv-f3hx. 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-v5m7-53cv-f3hx in your dependencies?
O3 detects GHSA-v5m7-53cv-f3hx across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.