reject hostname option injection via bracketed mount source#362
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A source like [-oProxyCommand=CMD]:/path passes the bracket-parsing check in find_base_path() and ends up as -oProxyCommand=CMD in the ssh argv. When sftp_server is a path, ssh gets a destination argument and executes the injected ProxyCommand before connecting. Reject hostnames starting with - after bracket stripping, and add -- before the hostname in the ssh command line so positional args can't be misread as options.
h4sh5
approved these changes
May 29, 2026
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A source like
[-oProxyCommand=CMD]:/pathpasses the bracket-parsing check infind_base_path()and ends up as-oProxyCommand=CMDin the ssh argv. Whensftp_serveris a path, ssh gets a destination argument and executes the injected ProxyCommand before connecting.Reject hostnames starting with
-after bracket stripping, and add--before the hostname in the ssh command line so positional args can't be misread as options.