CVE-2020-11810
Publication date 27 April 2020
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
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.
Status
Package | Ubuntu Release | Status |
---|---|---|
openvpn | ||
20.04 LTS focal |
Fixed 2.4.7-1ubuntu2.20.04.2
|
|
18.04 LTS bionic |
Fixed 2.4.4-2ubuntu1.5
|
|
16.04 LTS xenial |
Not affected
|
|
14.04 LTS trusty |
Not affected
|
Severity score breakdown
Parameter | Value |
---|---|
Base score | 3.7 · Low |
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 |
References
Related Ubuntu Security Notices (USN)
- USN-4933-1
- OpenVPN vulnerabilities
- 4 May 2021