CVE-2021-36368: 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.

Overview

Severity

Low (CVSS 3.7)

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

Exploit Status

Not Exploited

Patch Tuesday

2022-Mar

Released

2022-03-20

EPSS Score

0.53% (percentile: 67.3%)

FAQ

Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability? One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.

Affected Products (2)

Other

• 18888-16820
• 17826-16823

Revision History

• 2022-03-20: Information published.