Watchguard XTM 2 Series, XTM 5 Series, XTM 8 Series – Fireware XTM OS 11.4.2 – CSP10 Build # 336603
11.4.2 – CSP10 Build # 336603 Resolves the following issues:
BUG63867: SMTP proxy causes RFC5321 violation
BUG63136: HTTP proxy downloads stalling with Selective ACK support and IPS enabled
BUG65105: Generate incorrect iptable rule for setting of BOVPN 1 to 1 NAT with IP range object
BUG62883: resolved certd crashing/failure issue
You can request 11.4.2 – CSP10 Build # 336603 from Watchguard Support by logging a support case online, they should then be able to provide an ftp download link and appropriate credentials.
Please note that Watchguard CSP releases are cumulative so you should only need to apply the latest to ensure that you also have any previous fixes.