UNC4540
UNC4540 is a suspected Chinese threat actor targeting unpatched SonicWall Secure Mobile Access appliances to deploy custom malware that establishes long-term persistence for cyber espionage. The malware is designed to steal hashed credentials, provide shell access, and persist through firmware upgrades, utilizing a variant of the TinyShell backdoor. Mandiant has tracked UNC4540's activities back to 2021, noting their focus on maintaining access to compromised devices. The group's tactics are consistent with patterns observed in other Chinese threat actor campaigns targeting network devices for zero-day exploits.
CVEs in recent coverage
No CVEs named alongside this actor in the last 90 days.
Recent victims
No leak-site posts on record for this group.
Recent activity
No posts or advisories have named this actor recently.
References
From the MISP threat-actor galaxy, MITRE ATT&CK and RansomLook (CC BY 4.0). Activity is any post or advisory Watch Floor collected that names the actor or one of its aliases.