Almost exactly a year ago, security researchers uncovered one of the worst data breaches in modern history, if not ever: a Kremlin-backed hacking campaign that compromised the servers of network management provider SolarWinds and, from there, the networks of 100 of its highest-profile customers, including nine US federal agencies.
Nobelium—the name Microsoft gave to the intruders—was eventually expelled, but the group never gave up and arguably has only become more brazen and adept at hacking large numbers of targets in a single stroke. The latest reminder of the group’s proficiency comes from security firm Mandiant, which on Monday published research detailing Nobelium’s numerous feats—and a few mistakes—as it continued to breach the networks of some of its highest-value targets.