Ubuntu OpenSSH Critical Network Access Issue CVE-2026-35414 USN-8577

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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)

OpenSSH could allow unintended access to network services.

Software Description:

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

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)

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.

Ubuntu Security Notice USN-8577-1

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