CVE-2026-91766

Medium

Description

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 ).

SeverityMedium

CVSS5.9

Exploit probability—

Product

Php

PublishedSep 25, 2026

First seenSep 25, 2026

Weakness typeCWE-200Sensitive information exposure CWE-522CWE-522

How to fix

Update

php php8.2.34, 8.3.35, 8.4.26, 8.5.11 or later

Vendor advisories

github.com/php/php-src/security/advisories/GHSA-fpwc-w8rq-cr92

Affected products

Product	Affected versions	Fixed in
php php	8.2.0 ≤ v < 8.2.34, 8.3.0 ≤ v < 8.3.35, 8.4.0 ≤ v < 8.4.26, 8.5.0 ≤ v < 8.5.11	8.2.34, 8.3.35, 8.4.26, 8.5.11

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