CVE-2021-36368
Publication date 13 March 2022
Last updated 24 July 2024
Ubuntu priority
** DISPUTED ** An issue was discovered in OpenSSH before 8.9. If a client is using public-key authentication with agent forwarding but without -oLogLevel=verbose, and an attacker has silently modified the server to support the None authentication option, then the user cannot determine whether FIDO authentication is going to confirm that the user wishes to connect to that server, or that the user wishes to allow that server to connect to a different server on the user's behalf. NOTE: the vendor's position is "this is not an authentication bypass, since nothing is being bypassed."
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| openssh | 22.04 LTS jammy |
Not affected
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty |
Not affected
|
|
| openssh-ssh1 | 22.04 LTS jammy |
Not affected
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release |
Notes
seth-arnold
openssh-ssh1 is provided for compatibility with old devices that cannot be upgraded to modern protocols. Thus we may not provide security support for this package if doing so would prevent access to equipment.
mdeslaur
This CVE appears to have been disputed by upstream, marking as 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 | Low |
| Integrity impact | None |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |