Description
OpenVPN version 2.3.12 and newer is vulnerable to unauthenticated Denial of Service of server via received large control packet. Note that this issue is fixed in 2.3.15 and 2.4.2.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| OpenVPN Technologies | openvpn | 2.3.12 and newer | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | openvpn | 2.4.0-5 | — |
| Debian 13 | openvpn | 2.4.0-5 | — |
| Debian 12 | openvpn | 2.4.0-5 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | openvpn | 2.3.8-16.14.1 | SUSE-SU-2017:1622-1 |
| SLES 11 SP4 | openvpn | 2.0.9-143.47.3.1 | SUSE-SU-2017:2838-1 |
| SLES 11 SP3 | openvpn | 2.0.9-143.47.3.1 | SUSE-SU-2017:2838-1 |
| SLES 11 | openvpn-openssl1 | 2.3.2-0.9.1 | SUSE-SU-2017:1718-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP2 | openvpn | 2.3.8-16.14.1 | SUSE-SU-2017:1622-1 |
| SLES for SAP 11 SP4 | openvpn | 2.0.9-143.47.3.1 | SUSE-SU-2017:2838-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | openvpn | 2.0.9-143.47.3.1 | SUSE-SU-2017:2838-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.6 | openvpn | 2.4.2-r0 | — |
| Alpine v3.5 | openvpn | 2.3.15-r0 | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- OpenVPN 2.4.0 - Denial of Service EDB-41993 · dos · May 11, 2017 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 3
- SUSE-SU-2017:1718-1 Security update for openvpn-openssl1 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:2838-1 Security update for openvpn SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:1622-1 Security update for openvpn SUSE / openSUSE Security Updates · Feb 4, 2026
References
- 41993 exploit
- https://community.openvpn.net/openvpn/wiki/QuarkslabAndCryptographyEngineerAudits
- 1038473 vdb-entry
- 98444 vdb-entry