Methods and systems for content filtering of remote file-system access protocols are provided. According to one embodiment, a first set of Server Message Block/Common Internet File System (SMB/CIFS) protocol requests originated by a first process running on a client and relating to a file associated with a share of a server and a second set of SMB/CIFS protocol requests originated by a second process running on the client and relating to the file are transparently proxied by a gateway device. The existence or non-existence of malicious, dangerous or unauthorized content contained within the file is determined by the gateway device by (i) buffering data being read from or written to the file as a result of the first and second set of SMB/CIFS protocol requests into a shared file buffer; and (ii) performing content filtering on the shared file buffer when a scanning condition is satisfied.