They call it “stopping the bleeding”: the vital window to prevent an entire database from being ransacked by criminals or a production line grinding to a halt. When a call comes into the cybersecurity firm S-RM, headquartered on Whitechapel High Street in east London, a hacked business or institution may have just minutes to protect themselves. S-RM, which helped a high-profile retail client recover from a Scattered Spider cyber-attack has become a quiet, often word-of-mouth, success.