GHSA-fjx5-qpf4-xjf2
Parsing borsh messages with ZST which are not-copy/clone is unsound
Blast Radius
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Description
Affected versions of borsh cause undefined behavior when zero-sized-types (ZST) are parsed and the Copy/Clone traits are not implemented/derived. For instance if 1000 instances of a ZST are deserialized, and the ZST is not copy (this can be achieved through a singleton), then accessing/writing to deserialized data will cause a segmentation fault.
There is currently no way for borsh to read data without also providing a Rust type. Therefore, if you are not using ZST for serialization, then you are not affected by this issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | borsh | all versions | 1.0.0-alpha.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for borsh. 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 borsh to 1.0.0-alpha.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fjx5-qpf4-xjf2 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-fjx5-qpf4-xjf2 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-fjx5-qpf4-xjf2. 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-fjx5-qpf4-xjf2 in your dependencies?
O3 detects GHSA-fjx5-qpf4-xjf2 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.