GHSA-r24f-hg58-vfrw
unsafe-libyaml unaligned write of u64 on 32-bit and 16-bit platforms
Blast Radius
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Description
Affected versions allocate memory using the alignment of usize and write data to it of type u64, without using core::ptr::write_unaligned. In platforms with sub-64bit alignment for usize (including wasm32 and x86) these writes are insufficiently aligned some of the time.
If using an ordinary optimized standard library, the bug exhibits Undefined Behavior so may or may not behave in any sensible way, depending on optimization settings and hardware and other things. If using a Rust standard library built with debug assertions enabled, the bug manifests deterministically in a crash (non-unwinding panic) saying "ptr::write requires that the pointer argument is aligned and non-null".
No 64-bit platform is impacted by the bug.
The flaw was corrected by allocating with adequately high alignment on all platforms.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | unsafe-libyaml | all versions | 0.2.10 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for unsafe-libyaml. 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 unsafe-libyaml to 0.2.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r24f-hg58-vfrw 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-r24f-hg58-vfrw 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-r24f-hg58-vfrw. 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-r24f-hg58-vfrw in your dependencies?
O3 detects GHSA-r24f-hg58-vfrw 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.