CVE-2024-9440 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in slim-select. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for slim-select — see the affected versions and patch details below.
Slim Select 2.0 createOption "text" XSS
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.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-9440.
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
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.
slim-selectnpmDescription
Slim Select 2.0 versions through 2.9.0 are affected by a potential cross-site scripting vulnerability. In select.ts:createOption(), the text variable from the user-provided Options object is assigned to an innerHTML without sanitation. Software that depends on this library to dynamically generate lists using unsanitized user-provided input may be vulnerable to cross-site scripting, resulting in attacker executed JavaScript. At this time, no patch is available.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | slim-select | ≥ 2.0.0&&< 2.9.2 | 2.9.2npm install slim-select@2.9.2 |
Affected Products
slim selectslimselectjsResearch 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 slim-select, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update slim-select to 2.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-9440 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is CVE-2024-9440 in your dependencies?
Find it across npm, including transitive dependencies.