GHSA-mcrf-7hf9-f6q5
Unchecked vector pre-allocation
Blast Radius
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Description
Affected versions of this crate pre-allocate memory on deserializing raw buffers without checking whether there is sufficient data available. This allows an attacker to do denial-of-service attacks by sending small msgpack messages that allocate gigabytes of memory.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | rmpv | all versions | 0.4.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rmpv. 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 rmpv to 0.4.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mcrf-7hf9-f6q5 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-mcrf-7hf9-f6q5 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-mcrf-7hf9-f6q5. 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-mcrf-7hf9-f6q5 in your dependencies?
O3 detects GHSA-mcrf-7hf9-f6q5 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.