We’d like to provide an update on our investigation into the suspicious activity detected in our Fortra GoAnywhere MFT solution. Working with Unit 42, we have completed our investigation and have compiled a factual summary of the investigation, as well as continuous improvement actions Fortra is taking to further strengthen our systems and recommended actions customers can take to secure their data and improve their security posture using available features in the GoAnywhere MFT solution.
On 02 February 2023, an alert triggered in a Huntress-protected environment. At first glance, the alert itself was fairly generic - a combination of certutil using the urlcache flag to retrieve a remote resource and follow-on scheduled task creation - but further analysis revealed a more interesting set of circumstances. By investigating the event in question and pursuing root cause analysis (RCA), Huntress was able to link this intrusion to a recently-announced vulnerability as well as to a long-running post-exploitation framework linked to prominent ransomware groups.
On Thursday, February 2, 2023, security reporter Brian Krebs published a warning on Mastodon about an actively exploited zero-day vulnerability affecting on-premise instances of Fortra’s GoAnywhere MFT managed file transfer solution. Fortra (formerly HelpSystems) evidently published an advisory on February 1 behind authentication; there is no publicly accessible advisory.