More PDF exploits seen in wild

Adobe Reader and Acrobat flaws open way for further document attacks.

A string of vulnerabilities in Adobe's PDF viewing and editing software, disclosed late last week by Adobe and iDefense, have been exploited by malicious attacks using PDF files to launch malware.

The flaws, which include several buffer overflows, a library path vulnerability and a JavaScript handling issue, were unveiled last Thursday after Adobe released updated versions patching them, having been informed of the dangers by researchers at iDefense. Over the weekend documents using the vulnerabilities to launch malicious code were observed in the wild.

Trojans inserted into PDF files are likely to be distributed via email and on compromised websites, and while some software may detect such attacks using the same identification as a previous wave of PDF exploits, Symantec at least has dubbed the latest series of attacks 'Trojan.Zonebac'.

Users of Adobe software are advised to upgrade to the latest version to minimise exposure. An alert on the update is at Adobe here, with details of the vulnerabilities at iDefense here, here and here. A Secunia summary, labelling the flaws 'highly critical', is here, and a blog posting from Symantec on the attacks exploiting the vulnerabilities is here. More information on in-the-wild attacks using the exploit is at SANS here.