A newly discovered ransomware strain, Cephalus, is raising alarms in the cybersecurity community. As reported by Cybersecurity News, Cephalus exploits weak Remote Desktop Protocol (RDP) credentials, particularly those lacking multi-factor authentication (MFA), to infiltrate organizations.
But what makes Cephalus especially concerning is not just its entry point — it’s how it hides once inside.
Unlike traditional ransomware, Cephalus uses DLL sideloading to piggyback on legitimate software. In recent incidents, attackers disguised malicious files under SentinelOne’s legitimate security binaries to execute ransomware code undetected.
Once active, Cephalus disables Windows Defender protections, deletes system shadow copies to block file recovery, and ensures that victims cannot restore their systems without paying ransom. It also leverages MEGA cloud storage for data exfiltration, making it a double-extortion threat.
Perhaps most chillingly, the ransom notes reference real-world ransomware cases reported in the media, attempting to build urgency and credibility with victims.
Traditional endpoint protection tools rely heavily on a Detect and Respond approach. But Cephalus demonstrates how attackers are outpacing these methods by exploiting trusted software components to bypass detection entirely.
By the time these threats are “detected,” it’s already too late — files are encrypted, backups are deleted, and defenses are disabled.
Businesses can no longer rely solely on detection. They need Isolation and Containment to proactively block ransomware before it can execute.
This is where AppGuard changes the game. Instead of trying to recognize every possible threat, AppGuard prevents untrusted processes from executing in the first place.
Even if attackers gain access through RDP, AppGuard’s containment technology ensures that ransomware cannot sideload malicious DLLs or tamper with trusted software. With over 10 years of proven success in government and enterprise environments, AppGuard is now available for commercial use, providing small and mid-sized businesses with the same level of protection.
Cephalus ransomware is only the latest example of how fast cybercriminals are evolving. Defenders cannot afford to stay locked in an outdated Detect and Respond cycle.
It’s time to move to Isolation and Containment.
Business owners: talk with us at CHIPS about how AppGuard can protect your organization from threats like Cephalus — before they take hold.
Like this article? Please share it with others!