Flash Player Bug Exploited by Malicious Word Documents

Researchers have identified targeted attacks exploiting the Flash Player bug Adobe patched just last week.

Adobe patched the remote code execution vulnerability (CVE-2012-1535) in Flash Player which could cause the application to crash and potentially allow an attacker to take control of the compromised computer last Tuesday as part of its regularly scheduled update. At the time, the company said there were reports of the vulnerability being exploited in the wild in “limited attacks” using malicious Word documents.

Symantec researchers have observed such attacks since Aug. 10, Symantec’s Bhaskar Krishna wrote on the Symantec Intelligence blog. The Word document contains a malicious SWF file with ActionScript that utilizes heapspraying techniques using embedded shellcode, Krishna said. The Flash exploit is triggered by a font file.

“We would recommend that users keep their systems up-to-date with the latest security patch released by Adobe for this vulnerability,” Krishna wrote.

The attacks used different email subject lines, body text, and attachment file names, Krishna said. The names and subject lines cover political and other newsworthy items, topics of interest, as well as topics that may be of interest to specific industries and companies.

The email with subject line “Reports for AWEML” had an attachment called “AWE Platinum Partners.doc” with a random number prepended to the name. Another sample had the subject “Assessment of Enginering Design Competence – Questionnaire” with the attachment name “Jacobs Competenct Assessment” according to the Symantec post. Other subject lines included iPhone 5 battery rumors, Republican candidate for president Mitt Romney’s vice-president pick, and the London Olympics.

“A large number of attacks were sent on August 13,” Krishna found.

Adobe fixed only one vulnerability in Flash just over a week ago, and followed up with a larger security update this week fixing six additional issues in Flash Player across all platforms.

The second release was “a bit of a surprise for IT administrators,” said Wolfgang Kandek, CTO of Qualys, adding that last week’s release may actually have been “an out-of-band emergency fix to address a specific vulnerability under abuse in the wild and that could not be integrated with this bigger release.”