FreeBSD: VID-2a1b931f-2b86-11ec-8acd-c80aa9043978 (CVE-2021-41617): OpenSSH -- OpenSSH 6.2 through 8.7 failed to correctly initialise supplemental groups when executing an AuthorizedKeysCommand or AuthorizedPrincipalsCommand

OpenBSD Project reports: sshd(8) from OpenSSH 6.2 through 8.7 failed to correctly initialise supplemental groups when executing an AuthorizedKeysCommand or AuthorizedPrincipalsCommand, where a AuthorizedKeysCommandUser or AuthorizedPrincipalsCommandUser directive has been set to run the command as a different user. Instead these commands would inherit the groups that sshd(8) was started with. Depending on system configuration, inherited groups may allow AuthorizedKeysCommand/AuthorizedPrincipalsCommand helper programs to gain unintended privilege. Neither AuthorizedKeysCommand nor AuthorizedPrincipalsCommand are enabled by default in sshd_config(5).