VirusTotal

Iranian State-Sponsored Hackers Unveil Cavern C2 Framework: Multi-Format .NET Compilation Bypasses All Security Detection Tools

In July 2026, Check Point Research exposed Cavern Manticore, an Iranian MOIS-linked APT group, actively targeting Israeli IT providers and government entities with a sophisticated modular C2 framework called Cavern (also known as Cav3rn). Unlike previous Iranian groups that rely on public tools, this actor built an entirely custom .NET-based framework deliberately compiled into three incompatible binary formats—pure IL, mixed-mode C++/CLI, and .NET 8 Native AOT—to force analysts to maintain multiple reverse-engineering toolchains and dramatically increase operational costs. The framework achieves near-zero detection rates on VirusTotal by avoiding traditional obfuscation and instead weaponizing compilation formats themselves, with modules running in isolated AppDomains that leave no persistent artifacts. Attackers gain initial access through compromised RMM solutions such as SysAid, abusing legitimate update mechanisms to sideload the Cavern Agent disguised as uxtheme.dll via a WinDirStat DLL side-loading chain. Communication uses XOR encryption with Base64 encoding, fixed Edge User-Agent strings, custom headers, and a unique protocol syntax, while supporting hot updates and aggressive cleanup. The campaign coincides with parallel operations by MuddyWater against regional targets, highlighting Iran’s coordinated escalation in cyberspace and the growing threat of supply-chain trust abuse against MSPs and RMM platforms worldwide.