The threat intelligence group discovered the zero-day exploit during a "routine investigation" of Microsoft 365 Defender, its enterprise security software suite. SolarWinds had patched the vulnerabilities found by Microsoft on July 9, 2021. "The vulnerability exists in the latest Serv-U version 15.2.3 HF1 released May 5, 2021, and all prior versions. A threat actor who successfully exploited this vulnerability could run arbitrary code with privileges. An attacker could then install programs; view, change, or delete data; or run programs on the affected system," the company said in its.