Feeds

Gameover ZeuS adds nasty trick

Crypto to slip through firewalls

SANS - Survey on application security programs

The password-stealing ZeuS variant, Gameover, is now using encryption to get around perimeter security kit like firewalls and intrusion detection systems.

Malcovery's Gary Warner outlines the new behaviour of the malware at his blog, here, on the basis that the threat needed to be known beyond the circle of the company's customers.

Gameover ZeuS is a password-stealer, and has been spotted in attacks against Bitcoin users in China, and against CryptoLocker.

Warner writes that the .EXE file associated with Gameover ZeuS should by now be spotted by up-to-date security, so the malware's authors have begun encrypting the file and distributing it as a non-executable .ENC file.

Of course, a .ENC file isn't executable (which is why it could get a pass mark from security systems), so the authors have to find some way to decrypt it at the target. They do this via a file included in the phishing e-mail that kicks off an attack: “the .zip file attached to the email has a NEW version of UPATRE that first downloads the .enc file from the Internet and then DECRYPTS the file, placing it in a new location with a new filename, and then causing it both to execute and to be scheduled to execute in the future”, Warner writes.

Boldizsár Bencsáth, from CrySys Lab in Hungary, explains the encryption here. It's not terribly sophisticated (since the purpose isn't to hide sensitive data, but merely to present security systems with a file format they'll ignore): the file is compressed, then XORd with a 32-bit key. The e-mail dropper that infects victims simply reverses this process. ®

High performance access to file storage

More from The Register

next story
Obama allows NSA to exploit 0-days: report
If the spooks say they need it, they get it
Samsung Galaxy S5 fingerprint scanner hacked in just 4 DAYS
Sammy's newbie cooked slower than iPhone, also costs more to build
Putin tells Snowden: Russia conducts no US-style mass surveillance
Gov't is too broke for that, Russian prez says
Snowden-inspired crypto-email service Lavaboom launches
German service pays tribute to Lavabit
Mounties always get their man: Heartbleed 'hacker', 19, CUFFED
Canadian teen accused of raiding tax computers using OpenSSL bug
One year on: diplomatic fail as Chinese APT gangs get back to work
Mandiant says past 12 months shows Beijing won't call off its hackers
Call of Duty 'fragged using OpenSSL's Heartbleed exploit'
So it begins ... or maybe not, says one analyst
prev story

Whitepapers

Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Five 3D headsets to be won!
We were so impressed by the Durovis Dive headset we’ve asked the company to give some away to Reg readers.
SANS - Survey on application security programs
In this whitepaper learn about the state of application security programs and practices of 488 surveyed respondents, and discover how mature and effective these programs are.