---
id: CVE-2026-91766
title: >-
  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 HT…
summary: >-
  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 HT…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-200
  - CWE-522
  - CWE-201
vendor: PHP Group
product: ext-standard
affected:
  - ext-standard >= 8.2.* < 8.2.34
  - ext-standard >= 8.3.* < 8.3.35
  - ext-standard >= 8.4.* < 8.4.26
  - ext-standard >= 8.5.* < 8.5.11
published: '2026-09-25'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T21:17:24.673'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-91766'
references:
  - url: 'https://github.com/php/php-src/security/advisories/GHSA-fpwc-w8rq-cr92'
    label: security@php.net
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91766.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-91766'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2541649'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-91766'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-91766'
  - url: 'https://access.redhat.com/errata/RHSA-2026:70720'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ingestedAt: '2026-09-25T21:19:40.146Z'
patched:
  - hardened_images
---

## Overview

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 ).

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **RHSA-2026:70720** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:70720)
- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91766.json)