Hackers flip characters to disguise malware
Hackers are using a new trick to cloak malicious files by disguising their Windows file extensions to make them appear safe to download, a Czech security company warned today.
The exploit, dubbed "Unitrix" by Avast Software, abuses Unicode for right-to-left languages -- such as Arabic or Hebrew -- to mask Windows executable files (.exe) as innocuous graphic images (.jpg) or Word documents (.doc).
Unicode is the computer industry standard for representing text with alpha-numeric codes. The Unitrix exploit uses a hidden code (U+202E) that overrides right-to-left characters to display an executable file as something entirely different. Using that ploy, hackers can disguise a malicious file that ends with gpj.exe as a supposedly-safer photo_D18727_Collexe.jpg by reversing the last six characters of the former.
