CVE-2026-91766

When the http:// stream wrapper follows a redirect it forwards the user-supplied Authorization, Cookie and Proxy-Authorization headers unchanged, even when the redirect target is a different host, a different port, or a downgrade from HTTPS to HTTP. A server that can steer a redirect therefore receives credentials that were only meant for the original origin. This is the same class of issue that libcurl fixed in 7.58.0 ( CVE-2018-1000007 https://github.com/advisories/GHSA-g7x2-hrfp-pv5f ).

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/php/php-src/security/advisories/GHSA-fpwc-w8rq-cr92	Vendor Advisory Exploit

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:php:php::::::::
	cpe:2.3:a:php:php::::::::
	cpe:2.3:a:php:php::::::::
	cpe:2.3:a:php:php::::::::

History

23 Oct 2026, 13:46

Type	Values Removed	Values Added
First Time		Php php Php
CPE		cpe:2.3:a:php:php::::::::
References	~~() https://github.com/php/php-src/security/advisories/GHSA-fpwc-w8rq-cr92 -~~	() https://github.com/php/php-src/security/advisories/GHSA-fpwc-w8rq-cr92 - Vendor Advisory, Exploit

25 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-25 21:17

Updated : 2026-10-23 13:46

NVD link : CVE-2026-91766

Mitre link : CVE-2026-91766

CVE.ORG link : CVE-2026-91766

JSON object : View

Products Affected

php

php

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

CWE-522

Insufficiently Protected Credentials

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