[USN-6565-1] OpenSSH vulnerabilities

Marc Deslauriers marc.deslauriers at canonical.com
Wed Jan 3 19:38:12 UTC 2024

Ubuntu Security Notice USN-6565-1
January 03, 2024

openssh vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 23.10
- Ubuntu 23.04
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS


Several security issues were fixed in OpenSSH.

Software Description:
- openssh: secure shell (SSH) for secure access to remote machines


It was discovered that OpenSSH incorrectly handled supplemental groups when
running helper programs for AuthorizedKeysCommand and
AuthorizedPrincipalsCommand as a different user. An attacker could possibly
use this issue to escalate privileges. This issue only affected Ubuntu
20.04 LTS. (CVE-2021-41617)

It was discovered that OpenSSH incorrectly added destination constraints
when PKCS#11 token keys were added to ssh-agent, contrary to expectations.
This issue only affected Ubuntu 22.04 LTS, and Ubuntu 23.04.

It was discovered that OpenSSH incorrectly handled user names or host names
with shell metacharacters. An attacker could possibly use this issue to
perform OS command injection. (CVE-2023-51385)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 23.10:
   openssh-client                  1:9.3p1-1ubuntu3.2
   openssh-server                  1:9.3p1-1ubuntu3.2

Ubuntu 23.04:
   openssh-client                  1:9.0p1-1ubuntu8.7
   openssh-server                  1:9.0p1-1ubuntu8.7

Ubuntu 22.04 LTS:
   openssh-client                  1:8.9p1-3ubuntu0.6
   openssh-server                  1:8.9p1-3ubuntu0.6

Ubuntu 20.04 LTS:
   openssh-client                  1:8.2p1-4ubuntu0.11
   openssh-server                  1:8.2p1-4ubuntu0.11

In general, a standard system update will make all the necessary changes.

   CVE-2021-41617, CVE-2023-51384, CVE-2023-51385

Package Information:

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