CVE-2020-11810
Description
An issue was discovered in OpenVPN 2.4.x before 2.4.9. An attacker can inject a data channel v2 (P_DATA_V2) packet using a victim's peer-id. Normally such packets are dropped, but if this packet arrives before the data channel crypto parameters have been initialized, the victim's connection will be dropped. This requires careful timing due to the small time window (usually within a few seconds) between the victim client connection starting and the server PUSH_REPLY response back to the client. This attack will only work if Negotiable Cipher Parameters (NCP) is in use.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2020-11810
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2020-11810.html
Vendor advisory: arch — https://security.archlinux.org/ASA-202004-16
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| arch | fixed | 2.4.9-1 | |
| sles | affected | | |
| debian | bookworm | fixed | 2.4.9-1 |
| debian | bullseye | fixed | 2.4.9-1 |
| debian | forky | fixed | 2.4.9-1 |
| debian | sid | fixed | 2.4.9-1 |
| debian | trixie | fixed | 2.4.9-1 |
References
Verify integrity in audit chain (admin only). AS-IS.