# CVE-2025-2704: Denial of service in OpenVPN

> Remote attackers can cause denial of service in OpenVPN servers by corrupting and replaying packets during the TLS-crypt-v2 handshake.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Apr 2025
- **Updated:** 23 Oct 2025
- **Also known as:** ALPINE-CVE-2025-2704, CLEANSTART-2026-EP23751, DEBIAN-CVE-2025-2704, GHSA-5gwv-2q72-gxrm, OESA-2025-1396, OESA-2025-1397, SUSE-SU-2025:01508-1, SUSE-SU-2025:1508-1, UBUNTU-CVE-2025-2704, USN-7411-1, openSUSE-SU-2025:14979-1

## What is CVE-2025-2704?

CVE-2025-2704 is a high-severity denial of service vulnerability in OpenVPN, published on 2 Apr 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

OpenVPN version 2.6.1 through 2.6.13 in server mode using TLS-crypt-v2 allows remote attackers to trigger a denial of service by corrupting and replaying network packets in the early handshake phase

Weakness: CWE-754 (Improper Check for Unusual or Exceptional Conditions)

## Which versions are affected by CVE-2025-2704?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `openvpn` | SUSE:Linux Enterprise Module for Basesystem 15 SP6 | All versions | 2.6.8-150600.3.17.1 |
| `openvpn-dco` | SUSE:Linux Enterprise Module for Basesystem 15 SP6 | All versions | 2.6.8-150600.3.17.1 |
| `openvpn` | SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 2.6.8-150600.3.17.1 |
| `openvpn-dco` | SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 2.6.8-150600.3.17.1 |
| `openvpn` | openSUSE:Leap 15.6 | All versions | 2.6.8-150600.3.17.1 |
| `openvpn-dco` | openSUSE:Leap 15.6 | All versions | 2.6.8-150600.3.17.1 |
| `openvpn` | openSUSE:Tumbleweed | All versions | 2.6.14-1.1 |

Products: Openvpn Openvpn.

## How do I fix CVE-2025-2704?

Upgrade to a fixed version.

## Is CVE-2025-2704 being exploited?

There is no known exploitation of CVE-2025-2704 in the wild and no public exploit code.

## Other vulnerabilities in OpenVPN

- [CVE-2025-12106](https://insights.sbomify.com/CVE-2025-12106/): Memory corruption in OpenVPN (critical 9.1)
- [CVE-2024-5594](https://insights.sbomify.com/CVE-2024-5594/): Information disclosure in OpenVPN (critical 9.1)
- [CVE-2018-7544](https://insights.sbomify.com/CVE-2018-7544/): Cross-site request forgery in n/a (critical 9.1)
- [CVE-2006-1629](https://insights.sbomify.com/CVE-2006-1629/): Code injection in n/a (critical 9.0)
- [CVE-2024-4877](https://insights.sbomify.com/CVE-2024-4877/): Privilege escalation in OpenVPN (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-2704 and fix it if it is affected.

What it is: CVE-2025-2704 is a high-severity denial of service vulnerability in OpenVPN, published on 2 Apr 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-2704 in the wild and no public exploit code.

Affected product: OpenVPN. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-2704/ (Markdown: https://insights.sbomify.com/CVE-2025-2704/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-2704
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-2704
- OSV: https://osv.dev/vulnerability/CVE-2025-2704

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-2704/
Summaries are generated and may contain mistakes; the official description above is the record.