AsyncSSH: asyncio event-loop freeze via SSH maximum packet size = 0 in SSH_MSG_CHANNEL_OPEN / OPEN_CONFIRMATION

SummaryA malicious SSH server can wedge an AsyncSSH client, and an authenticatedclient can wedge an AsyncSSH server, by sending a channel maximum packetsize of 0 in SSHMSGCHANNELOPENCONFIRMATION server→client orSSHMSGCHANNELOPEN client→server. AsyncSSH stores the peer-supplied valueverbatim with ...

AsyncSSH: asyncio event-loop freeze via SSH maximum packet size = 0 in SSH_MSG_CHANNEL_OPEN / OPEN_CONFIRMATION

Summary A malicious SSH server can wedge an AsyncSSH client, and an authenticated client can wedge an AsyncSSH server, by sending a channel maximum packet size of 0 in SSHMSGCHANNELOPENCONFIRMATION server→client or SSHMSGCHANNELOPEN client→server. AsyncSSH stores the peer-supplied value verbatim...