OpenVPN, when using a 64-bit block cipher, makes it easier for remote attackers to obtain…
Priority LOW 35CWE-200Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA. Impact type from CWE-200.
Summary
OpenVPN, when using a 64-bit block cipher, makes it easier for remote attackers to obtain cleartext data via a birthday attack against a long-duration encrypted session, as demonstrated by an HTTP-over-OpenVPN session using Blowfish in CBC mode, aka a "Sweet32" attack.
Why it matters now
EPSS 0.0594 93rd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2016-6329
- 2026-10-03 Alias added: GHSA-w6pr-cm6j-f384
References
Advisory 7
- https://sweet32.info/
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05369403
- http://www-01.ibm.com/support/docview.wss?uid=swg21995039
- http://www-01.ibm.com/support/docview.wss?uid=swg21991482
- GLSA-201611-02
- https://community.openvpn.net/openvpn/wiki/SWEET32
- http://www-01.ibm.com/support/docview.wss?uid=nas8N1021697
More Openvpn vulnerabilities
- TI-2014-04453 Unquoted Windows search path vulnerability in the ptservice service prior to… CVSS 3.1MEDIUM 5.3
- TI-2022-00467 Authentication bypass in OpenVPN CVSS 3.1CRITICAL 9.8
- TI-2024-18509 Unrestricted file upload in OpenVPN 2 CVSS 3.1CRITICAL 9.8
- TI-2024-16468 The interactive service in OpenVPN 2.6.9 and earlier allows the OpenVPN service pipe to… CVSS 3.1HIGH 7.5
- TI-2023-25309 Use after free in OpenVPN 2 CVSS 3.1CRITICAL 9.8
- TI-2024-05196 OpenVPN before 2.6.11 does not santize PUSH_REPLY messages properly which an attacker… CVSS 3.1CRITICAL 9.1
Sources
- CVE-2016-6329 · CVE Program
- CVE-2016-6329 · NVD
- FIRST EPSS
- GHSA-w6pr-cm6j-f384 · GitHub Advisory Database · CC BY 4.0
- CVE-2016-6329 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences