RE: WinRAR SFX v5.21 - Remote Code Execution Vulnerability

["Popovici, Alejo \(LATCO - Buenos Aires\)" <apopovici () DELOITTE com>]

Well it's true what you are saying,
But it's also true that anti-virus software is fully aware of the usual way of executing malicious code through SFX 
archives. This could be a way of bypassing the anti-virus software thus avoiding detection.
In my opinion it should be fixed.

Kind regards,

Alejo Popovici
Consultor | ERS | Cyber Risk Services
Deloitte & Co. S.A.
Pte. Gral.J.D.Perón 646, 7piso, C1038AAN, Buenos Aires Argentina
apopovici () deloitte com | www.deloitte.com


-----Original Message-----
From: dev () rarlab com [mailto:dev () rarlab com]
Sent: Wednesday, September 30, 2015 8:05 AM
To: bugtraq () securityfocus com
Subject: Re: WinRAR SFX v5.21 - Remote Code Execution Vulnerability

I am WinRAR developer. We published the official comment on www.rarlab.com here:
http://rarlab.com/vuln_sfx_html.htm

This "vulnerability" is a non-issue. Why attempting to find some hackish esoteric way for a feature, which presents in 
SFX archives officially. Any SFX archive can run contained executable files, it is required for installers. Any SFX 
archive just like any exe file and any software installer is potentially dangerous for user computers and must be 
started only if received from a trustworthy source.

Self-extracting archives are .exe themselves, one of their basic functions is code execution for executables stored in 
archives. They also allow to run any kind of web downloaders, because it is needed for software installers. So that 
researcher discovered that self-extracting archives, which are exe themselves and designed to be able to run contained 
exe, can actually run exe. No surprise here and no new risks for users. All associated risks are already present in 
standard SFX functions and exe design.

 
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