CVE catalog
CVE-2025-3110
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
- Medium · CVSS 6.9
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.45% · Oct 27, 2026
A flaw in OpenVPN Access Server allows remote attackers to smuggle HTTP requests when the server operates behind a reverse proxy. The issue stems from the server accepting unstandardized bare line-feed sequences in HTTP headers. A Moderate flaw in OpenVPN Access Server allows remote HTTP request smuggling when deployed behind a reverse proxy. This occurs because the server improperly accepts bare line-feed sequences in HTTP headers, causing proxy misinterpretation. The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Cpe | openvpn_access_server | Not reported | Not reported | unknown |
| Cpe | openvpn_access_server | Not reported | Not reported | unknown |
Fixed-version evidence
OpenFactory catalog packages
No matching packages in this catalog.
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2025-3110]
- [https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-3110.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2246.json]
[CERT-Bund public advisories] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [Red Hat security advisories and VEX]