Paper: API-EPO

Posted by   Virus Bulletin on   Jul 14, 2014

Raul Alvarez studies the unique EPO methodology used by the W32/Daum file infector.

A few months ago, we published an article by Fortinet's Raul Alvarez on the Expiro file infector, which uses an EPO (entry-point obscuring) technique in an attempt to avoid heuristic detection.

In EPO, a file infector doesn't simply change the entry point of the infected executable - which is something that would be easy to detect. Rather, the malware 'patches', as it were, the executable to add a malicious component.

Today, we publish another paper by Raul Alvarez in which he looks at the W32/Daum file infector. Daum, which some AV vendors refer to as Lafee, is an old and relatively simple file infector. However, its unique EPO technique, in which all API calls are changed, makes it worth studying.

Remember that, as of this month, all papers published through Virus Bulletin are available free of charge. You can download this paper here in HTML format, or here as a PDF (no registration required).

Posted on 14 July 2014 by Martijn Grooten



Latest posts:

Analysis of malware responsible for sextortion spam that mines for Monero on the side

VB2019 Platinum partner Reason Cybersecurity presents a threat analysis report on the Save Yourself malware.

Guest blog: Threat intelligence – a unifying force of the future

In a guest blog post VB2019 Platinum partner Reason Cybersecurity looks to the future of threat intelligence.

Guest blog: Why we should be paying more attention to Linux threats

In a guest blog post VB2019 Silver partner Intezer outlines the importance of paying attention to Linux threats.

New Emotet spam campaign continues to bypass email security products

On Monday, the infamous Emotet malware resumed its spam campaign to spread the latest version of the malware. As before, the malware successfully bypasses many email security products.

Book review: Cyberdanger: Understanding and Guarding Against Cybercrime

Security researcher Paul Baccas reviews Eddy Willems' book 'Cyberdanger'.

We have placed cookies on your device in order to improve the functionality of this site, as outlined in our cookies policy. However, you may delete and block all cookies from this site and your use of the site will be unaffected. By continuing to browse this site, you are agreeing to Virus Bulletin's use of data as outlined in our privacy policy.