New Windows RAT Evades Detection for Weeks Using Corrupted DOS and PE Headers
May 29, 2025
Malware / Windows Security
Cybersecurity researchers have taken the wraps off an unusual cyber attack that leveraged malware with corrupted DOS and PE headers, according to new findings from Fortinet. The DOS (Disk Operating System) and PE (Portable Executable) headers are essential parts of a Windows PE file , providing information about the executable. While the DOS header makes the executable file backward compatible with MS-DOS and allows it to be recognized as a valid executable by the operating system, the PE header contains the metadata and information necessary for Windows to load and execute the program. "We discovered malware that had been running on a compromised machine for several weeks," researchers Xiaopeng Zhang and John Simmons from the FortiGuard Incident Response Team said in a report shared with The Hacker News. "The threat actor had executed a batch of scripts and PowerShell to run the malware in a Windows process." Fortinet said while it was unable to extract th...
