CVE-2026-67354
guzzlehttp/guzzle versions before 7.15.1 contain an information disclosure vulnerability in RedirectMiddleware.
Impact
guzzlehttp/guzzle versions before 7.15.1 contain an information disclosure vulnerability in RedirectMiddleware. When the optional allow_redirects.referer setting is enabled, the middleware copies the URI fragment (the portion after '#') from the referring request into the generated Referer header when following a same-scheme redirect (e.g., HTTPS to HTTPS). An attacker who controls the redirect destination can read this fragment from the incoming Referer header, potentially disclosing one-time login secrets, access tokens, state values, or other sensitive client data to a server never meant to receive it. The referer setting is disabled by default. Fixed in 7.15.1, which strips the fragment before generating the Referer value.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | guzzlehttp/guzzle | < 7.15.1 | 7.15.1 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-h95v-h523-3mw8
- https://github.com/guzzle/guzzle/security/advisories/GHSA-h95v-h523-3mw8
- https://github.com/guzzle/guzzle/pull/3901
- https://github.com/guzzle/guzzle/commit/7b68220d6543f6f80fe62e633361fc9d4ead14d4
- https://github.com/guzzle/guzzle/releases/tag/7.15.1
- https://nvd.nist.gov/vuln/detail/CVE-2026-67354
- https://www.vulncheck.com/advisories/guzzlehttp-guzzle-before-uri-fragment-disclosure-via-referer