CVE-2024-29041: expressjs express Open Redirect

Vulnerability summary

CVE-2024-29041 is a medium (CVSS 6.1) Open Redirect vulnerability in expressjs express. EPSS estimates a 0.79% chance of exploitation in the next 30 days, higher than 55.3% of scored vulnerabilities.

Timeline

1. 25-03-2024
   PublishedVulnerability first disclosed.
2. 02-08-2024
   Last modifiedVulnerability information updated.

Description

Express.js minimalist web framework for node. Versions of Express.js prior to 4.19.0 and all pre-release alpha and beta versions of 5.0 are affected by an open redirect vulnerability using malformed URLs. When a user of Express performs a redirect using a user-provided URL Express performs an encode [using `encodeurl`](https://github.com/pillarjs/encodeurl) on the contents before passing it to the `location` header. This can cause malformed URLs to be evaluated in unexpected ways by common redirect allow list implementations in Express applications, leading to an Open Redirect via bypass of a properly implemented allow list. The main method impacted is `res.location()` but this is also called from within `res.redirect()`. The vulnerability is fixed in 4.19.2 and 5.0.0-beta.3.

• CWE-601URL Redirection to Untrusted Site ('Open Redirect')The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.
• CWE-1286Improper Validation of Syntactic Correctness of InputThe product receives input that is expected to be well-formed - i.e., to comply with a certain syntax - but it does not validate or incorrectly validates that the input complies with the syntax.