GHSA-fmq6-4w57-2w3v is a high-severity (CVSS 8.4) Out-of-bounds Read vulnerability in wasm3. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for GHSA-fmq6-4w57-2w3v.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
wasm3🐍pywasm3📦github.com/shareup/wasm-interpreter-appleReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io, PyPI, SwiftURL packages — download data is not available via public APIs for these ecosystems.
Description
wasm3 at commit 139076a contains a memory leak in the Read_utf8 function.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | wasm3 | all versions | No fix |
| 🐍PyPI | pywasm3 | all versions | No fix |
| 📦SwiftURL | github.com/shareup/wasm-interpreter-apple | all versions | No fix |
Affected Products
wasm3wasm3_projectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for wasm3, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
The records we use list no patched version of wasm3 for GHSA-fmq6-4w57-2w3v. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.
Mitigate without a patch
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.
Frequently Asked Questions
Is GHSA-fmq6-4w57-2w3v in your dependencies?
Find it across crates.io, PyPI, SwiftURL, including transitive dependencies.