CVE-2024-29041 – express

Package

Manager: npm
Name: express
Vulnerable Version: >=0 <4.19.2 || >=5.0.0-alpha.1 <5.0.0-beta.3

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00043 pctl0.12194

Details

Express.js Open Redirect in malformed URLs ### Impact Versions of Express.js prior to 4.19.2 and pre-release alpha and beta versions before 5.0.0-beta.3 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()`. ### Patches https://github.com/expressjs/express/commit/0867302ddbde0e9463d0564fea5861feb708c2dd https://github.com/expressjs/express/commit/0b746953c4bd8e377123527db11f9cd866e39f94 An initial fix went out with `express@4.19.0`, we then patched a feature regression in `4.19.1` and added improved handling for the bypass in `4.19.2`. ### Workarounds The fix for this involves pre-parsing the url string with either `require('node:url').parse` or `new URL`. These are steps you can take on your own before passing the user input string to `res.location` or `res.redirect`. ### References https://github.com/expressjs/express/pull/5539 https://github.com/koajs/koa/issues/1800 https://expressjs.com/en/4x/api.html#res.location

Metadata

Created: 2024-03-25T19:40:26Z
Modified: 2025-07-21T16:57:31Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/03/GHSA-rv95-896h-c2vc/GHSA-rv95-896h-c2vc.json
CWE IDs: ["CWE-1286", "CWE-601"]
Alternative ID: GHSA-rv95-896h-c2vc
Finding: F100
Auto approve: 1