CVE-2024-51757 — happy-dom
Fix: capricorn86/happy-dom@5ee0b16CVE-2024-51757 is a Cross-site Scripting (XSS) vulnerability in happy-dom. A fix is available for happy-dom — see the affected versions and patch details below.
Fixes security vulnerability that allowed for server side code to be executed by a <script> tag
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.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-51757.
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.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
happy-domnpmDescription
happy-dom is a JavaScript implementation of a web browser without its graphical user interface. Versions of happy-dom prior to 15.10.2 may execute code on the host via a script tag. This would execute code in the user context of happy-dom. Users are advised to upgrade to version 15.10.2. There are no known workarounds for this vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | happy-dom | all versions | 15.10.2npm install happy-dom@15.10.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for happy-dom, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update happy-dom to 15.10.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-51757 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-51757 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-51757. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-51757 in your dependencies?
O3 Security finds CVE-2024-51757 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.