CVE-2025-3110 - Vulnerability Details - OpenCVE

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

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact Low

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

OpenVPN

Access Server

unaffected

Version	Status	Constraints
`2.7.2`	affected	≤ 3.1.0

No data.

No data.

No data.

Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://openvpn.net/as-docs/as-3-2-release-notes.html

History

Wed, 08 Jul 2026 17:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Wed, 08 Jul 2026 16:30:00 +0000

Type	Values Removed	Values Added
Description		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
Weaknesses		CWE-444
References		https://openvpn.net/as-docs/as-3-2-release-notes.html
Metrics		cvssV4_0 `{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: OpenVPN

Published: 2026-07-08T16:19:38.337Z

Updated: 2026-07-08T16:30:47.077Z

Reserved: 2025-04-02T07:56:08.672Z

Link: CVE-2025-3110

Vulnrichment

Updated: 2026-07-08T16:30:04.925Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-444

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