Adobe Reader, one of the most popular targets for cyber-criminals, has been slammed with another zero day exploit that can allegedly bypass the sandbox implemented in version 10.
According to the team at Group-IB, the exploit is now on sale on underground markets for prices between $30,000 and $50,000 as part of a custom-made version of the popular Blackhole crimeware kit. The exploitation mechanism goes like this: malicious code that exploits the Adobe vulnerability is added to a PDF file hosted on a website.
As a victim clicks a link to the file, the Reader plugin attempts to load the PDF file. When it is loaded, arbitrary shellcode is executed, and bypasses the security container implemented in Reader versions 10 and above.
â€œThe vulnerability has some limitations, for example it could be successfully exploited only after the user will close the browser and restart it. Another variant is to organize interaction between the victim and the malformed PDF-document,â€ Komarov said. â€œEither way, the vulnerability is has very significant vector to be spread with bypassing of internal Adobe X sandbox, which is appealing for cybercrime gangs because in the past there was no documented method of how to bypass it with shellcode execution.â€
The discovery of a zero-day exploit of this magnitude also poses serious risks for enterprises, who frequently deal with PDF files sent via e-mail as part of their day-to-day business. While exe files are filtered at the gateway firewall, PDF files are allowed to get in unhindered bundled with missed spam. Plus, as the regular patch cycle in an enterprise is once every 30 days, the attackers would have a pretty large window of opportunity between the time that Adobe comes out with a fix and the actual deployment across the company.
Bottom line: use an antivirus solution with built-in anti-spam and donâ€™t forget to double-check the origin of an e-mail before popping the attachment open.