GHSA-mwq8-fjpf-c2gr
HIGHPrototype pollution in matrix-js-sdk (part 2)
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
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
matrix-js-sdknpmDescription
Impact
In certain configurations, data sent by remote servers containing special strings in key locations could cause modifications of the Object.prototype, disrupting matrix-js-sdk functionality, causing denial of service and potentially affecting program logic.
(This is part 2, where CVE-2022-36059 / GHSA-rfv9-x7hh-xc32 is part 1. Part 2 covers remaining vectors not covered by part 1, found in a codebase audit scheduled after part 1.)
Patches
The issue has been patched in matrix-js-sdk 24.0.0.
Workarounds
None.
References
- Release blog post
- The advisory GHSA-rfv9-x7hh-xc32 (CVE-2022-36059) refers to an initial set of vulnerable locations discovered and patched in matrix-js-sdk 19.4.0. We opted not to disclose that advisory while we performed an audit of the codebase and are now disclosing it jointly with this one.
For more information
If you have any questions or comments about this advisory please email us at security at matrix.org.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | matrix-js-sdk | all versions | 24.0.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for matrix-js-sdk. 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 matrix-js-sdk to 24.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mwq8-fjpf-c2gr 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-mwq8-fjpf-c2gr 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-mwq8-fjpf-c2gr. 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-mwq8-fjpf-c2gr in your dependencies?
O3 detects GHSA-mwq8-fjpf-c2gr across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.