---
id: CVE-2026-90711
title: >-
  proxy-addr is a Node.js module that determines a request's client address
  behind trusted reverse proxies, and it backs Express req.ip and req.ips
summary: >-
  proxy-addr is a Node.js module that determines a request's client address
  behind trusted reverse proxies, and it backs Express req.ip and req.ips. In
  versions 1.1.0 through 2.0.7, a trust subnet written in IPv4-mapped IPv6
  notation with …
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-290
  - CWE-348
  - CWE-697
vendor: proxy-addr
product: proxy-addr
affected:
  - proxy-addr >= 1.1.0 < 2.0.8
published: '2026-09-15'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:40:00.317'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90711'
references:
  - url: 'https://cna.openjsf.org/security-advisories.html'
    label: ce714d77-add3-4f53-aff5-83d477b104bb
  - url: >-
      https://github.com/jshttp/proxy-addr/security/advisories/GHSA-jqcg-44mw-7w3h
    label: ce714d77-add3-4f53-aff5-83d477b104bb
tags:
  - nvd
  - cve.org
epss: 0.00332
epssPercentile: 0.23721
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-15T14:46:09.894513Z'
ingestedAt: '2026-09-15T07:33:29.276Z'
---

## Overview

proxy-addr is a Node.js module that determines a request's client address behind trusted reverse proxies, and it backs Express req.ip and req.ips. In versions 1.1.0 through 2.0.7, a trust subnet written in IPv4-mapped IPv6 notation with an IPv4-sized prefix, such as ::ffff:10.0.0.0/8 instead of the correct ::ffff:10.0.0.0/104, is accepted without error but trusts every IPv4 address on the internet rather than the block it names. Because the socket peer then becomes trusted at hop 0, any unauthenticated client can supply an arbitrary X-Forwarded-For header and control the address the application reads, which defeats IP-based access control, rate limiting, geolocation, and audit logging. This is a fail-open regression introduced in version 1.1.0. The issue is fixed in proxy-addr 2.0.8, and users should upgrade to 2.0.8 or later. As a workaround, ensure any IPv4-mapped IPv6 trust subnet uses a prefix length of at least 97, or express the range in plain IPv4 notation.

## Remediation

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