CVE-2026-67354

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/guzzle/guzzle/security/advisories/GHSA-h95v-h523-3mw8
https://www.vulncheck.com/advisories/guzzlehttp-guzzle-before-uri-fragment-disclosure-via-referer

Configurations

No configuration.

History

01 Aug 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-08-01 13:17

Updated : 2026-08-01 13:17

NVD link : CVE-2026-67354

Mitre link : CVE-2026-67354

CVE.ORG link : CVE-2026-67354

JSON object : View

Products Affected

No product.

CWE

CWE-201

Insertion of Sensitive Information Into Sent Data

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