---
id: CVE-2025-3110
title: >-
  OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences
  inside HTTP header values, allowing remote attackers to perform HTTP request
  smuggling when deployed behind a reverse proxy
summary: >-
  OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences
  inside HTTP header values, allowing remote attackers to perform HTTP request
  smuggling when deployed behind a reverse proxy
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'
cwe:
  - CWE-444
vendor: openvpn
product: openvpn_access_server
affected:
  - 'openvpn_access_server >= 2.7.2, <= 3.1.0'
published: '2026-07-08'
updated: '2026-09-29'
sourceUpdated: '2026-09-29T19:10:00.160'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-3110'
references:
  - url: 'https://openvpn.net/as-docs/as-3-2-release-notes.html'
    label: security@openvpn.net
tags:
  - nvd
epss: 0.00445
epssPercentile: 0.36266
ingestedAt: '2026-09-29T19:44:04.103Z'
---

## Overview

OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences inside HTTP header values, allowing remote attackers to perform HTTP request smuggling when deployed behind a reverse proxy

## Affected

- `openvpn_access_server >= 2.7.2, <= 3.1.0`

## Remediation

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