CVE-2020-5263
MEDIUMCVE-2020-5263 is a medium-severity (CVSS 4.9) CWE-522 vulnerability in auth0-js. O3 Security confirms whether CVE-2020-5263 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Information disclosure through error object in auth0.js
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
auth0-jsnpmDescription
auth0.js (NPM package auth0-js) greater than version 8.0.0 and before version 9.12.3 has a vulnerability. In the case of an (authentication) error, the error object returned by the library contains the original request of the user, which may include the plaintext password the user entered. If the error object is exposed or logged without modification, the application risks password exposure. This is fixed in version 9.12.3
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | auth0-js | ≥ 8.0.0&&< 9.13.2 | 9.13.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for auth0-js. 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 auth0-js to 9.13.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-5263 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 CVE-2020-5263 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 CVE-2020-5263. 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-2020-5263 in your dependencies?
O3 detects CVE-2020-5263 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.