Rar - CmdExtract::UnstoreFile Integer Truncation Memory Corruption

Author: Google Security Research
type: dos
platform: multiple
port: 
date_added: 2015-12-10 
date_updated: 2015-12-10 
verified: 1 
codes: OSVDB-131512 
tags: 
aliases:  
screenshot_url:  
application_url: 

Source: https://code.google.com/p/google-security-research/issues/detail?id=550

The attached file crashes in CmdExtract::UnstoreFile because the signed int64 DestUnpSize is truncated to an unsigned 32bit integer. Perhaps CmdExtract::ExtractCurrentFile should sanity check Arc.FileHead.UnpSize early.

I observed this crash in Avast Antivirus, but the origin of the code appears to be the unrar source distribution. I imagine many other antiviruses will be affected, and presumably WinRAR and other archivers.

Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/38930.zip