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Alerts This Week
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Ubuntu OpenSSH Critical Network Access Issue CVE-2026-35414 USN-8577-1

ubuntu
Calendar Grey July 21, 2026
Scroller Ubuntu
OpenSSH on Ubuntu 16.04 LTS has a critical access flaw; update recommended for enhancing system security.
OpenSSH could allow unintended access to network services.

Summary

OpenSSH could allow unintended access to network services.

Software Description:

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

Details:

USN-8222-1 fixed a vulnerability in OpenSSH. This update provides the

corresponding fix for Ubuntu 16.04 LTS.

Original advisory details:

Vladimir Tokarev discovered that OpenSSH incorrectly handled certificates

with the principal name containing a comma character when using user-trusted

CA keys in authorized_keys and an authorized_keys principals="" option

that lists more than one principal. This could result in inappropriate

principal matching, contrary to expectations. (CVE-2026-35414)

Topics%20covered

Topics Covered

security advisory critical Ubuntu openssh network access user-trusted

Update Instructions

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

Ubuntu 16.04 LTS
  openssh-server                  1:7.2p2-4ubuntu2.10+esm9
                                  Available with Ubuntu Pro

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

References

https://ubuntu.com/security/notices/USN-8577-1

CVE-2026-35414

Severity
critical
Lowest
Low
Medium
High
Critical

Ubuntu Security Notice USN-8577-1

Topics%20covered

Topics Covered

security advisory critical Ubuntu openssh network access user-trusted

Package Information

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