Twitter 上看到 Gasol 轉推的 OpenSSH 安全性問題:「OpenSSH Security Advisory: gcmrekey.adv」。
開頭就直接寫:
If exploited, this vulnerability might permit code execution with the privileges of the authenticated user and may therefore allow bypassing restricted shell/command configurations.
這噴飯了… OpenSSH 的安全性相當強,這次出這種包… XDDD
影響的範圍是 OpenSSH 6.2 與 6.3,並且 OpenSSL 有編 AES-GCM:
OpenSSH 6.2 and OpenSSH 6.3 when built against an OpenSSL that supports AES-GCM.
如果不允許升級到 OpenSSH 6.4,那麼暫時性的解法是不允許 AES-GCM,在 /etc/ssh/sshd_config
內可以設:
Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc
結果 FreeBSD 9.2 看起來在範圍內中槍,先上 workaround 再來等 freebsd-update 提供的修正吧…