D-Link botnet

Extracting binaries from a botnet of compromised NAS devices

01-07-2018

SEARCH-LAB security assessment

The 53 unique vulnerabilities identified in 2014 are now actively being exploited in the wild. Remote attackers can execute arbitrary code and gain full control over the device.

Implants

automatic decompilation

The automatic decompilation of the implants is trivial.

implant.c

The names of the functions are clearly visible and give an exact indication of what the implant does, the IP of the C&C is directly exposed, the download of the secondary stage was not protected.

IP of the C&C

Despite the reverse engineering being trivial on them all detection amongst av-engines varies greatly, as is shown by the VirusTotal results.

VirusTotal results

etp.db is an encrypted sqlite database, and is the only thing that the attackers protected.

Samples

2pn4yRMh8T1G.so - FXx3CyvEoz9E.so - IWBtRNuqVS.so : e29afce3afe992b57c7b03660d4ec5fcdcf2b694f580d221121d9cd9e04e15d5

DsGn8v1r.so - ZI42LA3R.so : 8f4967b653b6e7e00943e7a96d9126a0b734b9c0613029487179fab76f4aa4c0

8sy2b96E9K.so : dfa64db65f854441bd094acf3a48ecf858848c79f8f312e6fec0ade8e8fe43dd

wLl7EhHw.so : a725aad4f05628d2c49d46ee6070aec0a01f70cbac720ccee54cbab5524bee53

ilQqCI+J.dms : a14dbeea55221daf5344ab5f5ca98dd209f415cae6cb168c62a39db32b2d77fa

etp.db : b2b88659556adf9510507ee6187e3af4b52bd49e04cb4247527dd60cf4ce72bc

etp2.db : 3f7e34d6c13d10730a24f3834db01f290961e4a594b4b13f927c387d49f5368f

etp3.db : c4e3e2443dbc6578cc8f7e4614dc9591e315da65aaa68a2fee81ef8a623504a3