CVE-2020-11810
Published: 27 April 2020
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.
Priority
Status
Package | Release | Status |
---|---|---|
openvpn Launchpad, Ubuntu, Debian |
groovy |
Not vulnerable
(2.4.9-3ubuntu1)
|
hirsute |
Not vulnerable
(2.5.1-1ubuntu1)
|
|
bionic |
Released
(2.4.4-2ubuntu1.5)
|
|
eoan |
Ignored
(end of life)
|
|
focal |
Released
(2.4.7-1ubuntu2.20.04.2)
|
|
trusty |
Not vulnerable
(code not present)
|
|
upstream |
Released
(2.4.9-1)
|
|
xenial |
Not vulnerable
(code not present)
|
|
Patches: upstream: https://github.com/OpenVPN/openvpn/commit/37bc691e7d26ea4eb61a8a434ebd7a9ae76225ab upstream: https://github.com/OpenVPN/openvpn/commit/f7b318f811bb43c0d3aa7f337ec6242ed2c33881 (2.4) |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 3.7 |
Attack vector | Network |
Attack complexity | High |
Privileges required | None |
User interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | None |
Availability impact | Low |
Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |