1. Ubuntu Security Notices
  2. USN-6565-1

USN-6565-1: OpenSSH vulnerabilities

Publication date

3 January 2024

Overview

Several security issues were fixed in OpenSSH.

Releases

Packages

  • openssh - secure shell (SSH) for secure access to remote machines

Details

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.
(CVE-2023-51384)

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)

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.
(CVE-2023-51384)

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

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
23.10 mantic openssh-client –  1:9.3p1-1ubuntu3.2
openssh-server –  1:9.3p1-1ubuntu3.2
23.04 lunar openssh-client –  1:9.0p1-1ubuntu8.7
openssh-server –  1:9.0p1-1ubuntu8.7
22.04 jammy openssh-client –  1:8.9p1-3ubuntu0.6
openssh-server –  1:8.9p1-3ubuntu0.6
20.04 focal openssh-client –  1:8.2p1-4ubuntu0.11
openssh-server –  1:8.2p1-4ubuntu0.11

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References

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