GHSA-h9rv-jmmf-4pgx
MEDIUMGHSA-h9rv-jmmf-4pgx is a medium-severity (CVSS 4.2) Cross-site Scripting (XSS) vulnerability in serialize-javascript. O3 Security confirms whether GHSA-h9rv-jmmf-4pgx is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cross-Site Scripting in serialize-javascript
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
serialize-javascriptnpmDescription
Versions of serialize-javascript prior to 2.1.1 are vulnerable to Cross-Site Scripting (XSS). The package fails to sanitize serialized regular expressions. This vulnerability does not affect Node.js applications.
Recommendation
Upgrade to version 2.1.1 or later.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | serialize-javascript | all versions | 2.1.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for serialize-javascript. 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 serialize-javascript to 2.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h9rv-jmmf-4pgx 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-h9rv-jmmf-4pgx 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-h9rv-jmmf-4pgx. 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-h9rv-jmmf-4pgx in your dependencies?
O3 detects GHSA-h9rv-jmmf-4pgx across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.