Pinging All The Way
A week or two ago reader Norris Carden submitted a malicious document. This document is another "sleeper": it waits a couple of minutes before downloading and executing a malicious payload.
The trick used here is to start a ping command (from VBA macros) that will take several minutes to execute: cmd.exe /C ping 8.8.8.8 -n 250 > nul
This command does 250 pings to Google DNS 8.8.8.8. It will take around 4 minutes and 10 seconds to execute. And after that, the VBA code downloads and executes malware.
Didier Stevens
Microsoft MVP Consumer Security
blog.DidierStevens.com DidierStevensLabs.com
NVISO
Click HERE to learn more about classes Didier is teaching for SANS
×
Diary Archives

Comments
Anonymous
Dec 25th 2016
9 years ago
Anonymous
Dec 25th 2016
9 years ago
Evade detection by time-limited, automatic dynamic analysis.
Which can in turn be defeated by killing the ping process.
Anonymous
Dec 25th 2016
9 years ago
Anonymous
Dec 25th 2016
9 years ago
Anonymous
Dec 25th 2016
9 years ago