Adobe confirmed late on Monday that hackers are exploiting a vulnerability in the most up-to-date version of its PDF viewing and editing applications.
"This afternoon, Adobe received reports of a vulnerability in Adobe Reader and Acrobat 9.2 and earlier versions being exploited in the wild," said David Lenoe, the company's security program manager, on the Adobe's product security incident response team (PSIRT) blog. "We are currently investigating this issue and assessing the risk to our customers."
Computerworld searched security mailing lists and sites, including Bugtraq, Full Disclosure and milw0rm.com but turned up no reports of exploits in the wild.
An Adobe representative described why, saying, "The reports came to PSIRT directly from partners in the security community," Adobe's Wiebke Lips said. "As of this moment, I have not seen any public reports aside from the Adobe PSIRT blog post that just went live."
Both Lenoe and Lips promised that Adobe would publish more information of the bug in Reader 9.2 and Acrobat 9.2 when they have details from its investigation.
Adobe updated Reader and Acrobat to versions 9.2 in mid-October, when it patched nearly 30 vulnerabilities in the popular programs.
The company has struggled this year to keep up with a rising tide of Reader and Acrobat flaws. In March, Adobe quashed a PDF bug that attackers had been using for more than two months, patched Reader and Acrobat again in May to block another zero-day and fixed a Flash-related PDF flaw in July.
The update to 9.2 was the fourth during 2009 that plugged at least one hole already being used by hackers, a vulnerability often described as a "zero-day" to indicate that a patch was not available when attacks started.
Several months ago, Adobe committed to delivering Reader and Acrobat security updates every three months as part of a renewed effort to lock down its software. According to that schedule, Adobe should be patching its PDF programs next month.
Last week, Adobe updated Flash Player to patch seven vulnerabilities.