Summary
Overview
Between versions 8.0.0 and 9.13.1(inclusive), 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.
Am I affected?
You are affected by this vulnerability if all of the following conditions apply:
- You are using Auth0.js version between 8.0.0 and 9.13.1(inclusive).
- You store or display error objects without filtering.
How to fix that?
Developers should upgrade auth0.js to version 9.13.2 or later where user inputted passwords are masked in errors. If upgrading is not possible, a temporary fix may include not storing the error object or displaying it publicly without modification.
Will this update impact my users?
This fix patches the Auth0.js and may require changes in application code due to password no longer available in error object, but it will not impact your users, their current state, or any existing sessions.
Impact
CVE-2020-5263 has a CVSS score of 5.5 (High). The vector is requires local access, high privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (9.13.2); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2020-5263? CVE-2020-5263 is a high-severity security vulnerability in auth0-js (npm), affecting versions >= 8.0.0, < 9.13.2. It is fixed in 9.13.2.
- How severe is CVE-2020-5263? CVE-2020-5263 has a CVSS score of 5.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of auth0-js are affected by CVE-2020-5263? auth0-js (npm) versions >= 8.0.0, < 9.13.2 is affected.
- Is there a fix for CVE-2020-5263? Yes. CVE-2020-5263 is fixed in 9.13.2. Upgrade to this version or later.
- Is CVE-2020-5263 exploitable, and should I be worried? Whether CVE-2020-5263 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2020-5263 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2020-5263? Upgrade
auth0-jsto 9.13.2 or later.