Ubuntu Security Notice 7108-1 – Fabian Bäumer, Marcus Brinkmann, and Joerg Schwenk discovered that AsyncSSH did not properly handle the extension info message. An attacker able to intercept communications could possibly use this issue to downgrade the algorithm used for client authentication. Fabian Bäumer, Marcus Brinkmann, and Joerg Schwenk discovered that AsyncSSH did not properly handle the user authentication request message. An attacker could possibly use this issue to control the remote end of an SSH client session via packet injection/removal and shell emulation.Ubuntu Security Notice 7108-1 – Fabian Bäumer, Marcus Brinkmann, and Joerg Schwenk discovered that AsyncSSH did not properly handle the extension info message. An attacker able to intercept communications could possibly use this issue to downgrade the algorithm used for client authentication. Fabian Bäumer, Marcus Brinkmann, and Joerg Schwenk discovered that AsyncSSH did not properly handle the user authentication request message. An attacker could possibly use this issue to control the remote end of an SSH client session via packet injection/removal and shell emulation.