Skip to content

[Security] Bump express from 4.19.1 to 4.19.2

Dependabot requested to merge dependabot-npm_and_yarn-express-4.19.2 into master

Bumps express from 4.19.1 to 4.19.2. This update includes a security fix.

Vulnerabilities fixed

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 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

... (truncated)

Patched versions: 4.19.2 Affected versions: < 4.19.2

Release notes

Sourced from express's releases.

4.19.2

What's Changed

Full Changelog: https://github.com/expressjs/express/compare/4.19.1...4.19.2

Changelog

Sourced from express's changelog.

4.19.2 / 2024-03-25

  • Improved fix for open redirect allow list bypass
Commits


Dependabot commands
You can trigger Dependabot actions by commenting on this MR
  • $dependabot recreate will recreate this MR rewriting all the manual changes and resolving conflicts

Merge request reports

Loading