Security vendors (like Malwarebytes ) are actively updating their engines to ignore the header and perform "brute-force" decompression.
Specifically, this often refers to the technique (tracked as CVE-2026-0866), a method used to bypass antivirus detection by manipulating the file header to hide compressed malware within a seemingly "uncompressed" archive. 🛡️ Understanding the "Frozen" ZIP Vulnerability PROTHOM(Frozen)zip
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. Security vendors (like Malwarebytes ) are actively updating
to explain why it flagged a "PROTHOM" file. to explain why it flagged a "PROTHOM" file
Use tools to verify the SHA-256 hash of any utility you download against official sites like 7-Zip.org . If you'd like to investigate further, I can help you: Check a specific file hash to see if it is a known threat.