Prothom(frozen)zip Apr 2026

The vulnerability exploits the way different software reads the ZIP file structure (Local File Header vs. Central Directory). Normal ZIP Behavior "Frozen" / Zombie ZIP Behavior Correctly lists "Deflate" compression. Claims "Stored" (no compression). Actual Data Compressed payload. Compressed payload (mismatch). Scanner Unzips and scans the payload. Skips unzipping; scans only the encrypted/raw bits. Effect Malware is detected. Malware is missed. ⚠️ Security Recommendations

The term "Frozen" or "Zombie" in this context describes a ZIP file whose metadata has been "frozen" or locked into an incorrect state to trick security software. PROTHOM(Frozen)zip

These files are often distributed via fake downloads (e.g., fake 7-Zip installers or "cracked" software). The vulnerability exploits the way different software reads

to explain why it flagged a "PROTHOM" file. PROTHOM(Frozen)zip