An errata patch for sshd(8) has been released for OpenBSD 6.8 and OpenBSD 6.9.
sshd(8) from OpenSSH 6.2 (OpenBSD 5.3) through 8.7 (OpenBSD 6.9) 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). Binary updates for the amd64, i386 and arm64 platform are available via the syspatch utility. Source code patches can be found on the respective errata page: https://www.openbsd.org/errata68.html https://www.openbsd.org/errata69.html
