GHSA-h3cq-j957-vhxg is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in fullpage.js. 1 public exploit reference exists, so weaponization risk is real. A fix is available for fullpage.js — see the affected versions and patch details below.
Cross-site Scripting in fullpage.js
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.
How urgent is this, really
GHSA-h3cq-j957-vhxg plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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.
fullpage.jsnpmDescription
using fullpage.js you can create a anchor tag . But when put href in anchor then it does not sanitize the url which allow for a break in the context of anchor element and can add our new element.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | fullpage.js | all versions | 4.0.5npm install fullpage.js@4.0.5 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fullpage.js, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update fullpage.js to 4.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h3cq-j957-vhxg 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 GHSA-h3cq-j957-vhxg can be triaged on real exposure rather than presence alone.
Tailored to GHSA-h3cq-j957-vhxg. 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-h3cq-j957-vhxg in your dependencies?
O3 Security finds GHSA-h3cq-j957-vhxg across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.