GHSA-rv95-896h-c2vc

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Source
https://github.com/advisories/GHSA-rv95-896h-c2vc
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/03/GHSA-rv95-896h-c2vc/GHSA-rv95-896h-c2vc.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-rv95-896h-c2vc
Aliases
Related
Published
2024-03-25T19:40:26Z
Modified
2024-03-25T22:24:57Z
Severity
  • 6.1 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N CVSS Calculator
Summary
Express.js Open Redirect in malformed URLs
Details

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

https://github.com/expressjs/express/pull/5539 https://github.com/koajs/koa/issues/1800 https://expressjs.com/en/4x/api.html#res.location

Database specific 
{
    "nvd_published_at": "2024-03-25T21:15:46Z",
    "cwe_ids": [
        "CWE-1286",
        "CWE-601"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2024-03-25T19:40:26Z"
}
References

Affected packages

npm / express

Package

Name
express
View open source insights on deps.dev
Purl
pkg:npm/express

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.19.2

npm / express

Package

Name
express
View open source insights on deps.dev
Purl
pkg:npm/express

Affected ranges

Type
SEMVER
Events
Introduced
5.0.0-alpha.1
Fixed
5.0.0-beta.3