"A critical vulnerability exists in the current versions of Flash Player (v126.96.36.199 and v10.0.22.87) for Windows, Macintosh and Linux operating systems, and the authplay.dll component that ships with Adobe Reader and Acrobat v9.x for Windows, Macintosh and UNIX operating systems," the company said. "This vulnerability (CVE-2009-1862) could cause a crash and potentially allow an attacker to take control of the affected system."
US-CERT, which operates in conjunction with the Department of Homeland Security, warned users to disable Flash in Adobe Reader 9 on Windows computers and either to disable Flash Player or to enable only known safe Flash content.
Adobe said it will have fixes ready on July 30, for Flash Player, and on July 31 for Reader and Acrobat. In the meantime, it would probably be wise to heed US-CERT's advice: SANS Internet Storm Center handler John Bambenek reports that the vulnerability is being actively exploited.
Only a few malicious sites are currently serving the exploit, he said in a blog post, "but we confirmed that the links have been injected in legitimate Web sites to create a drive-by attack, as expected."
"Flash Player users should exercise caution in browsing untrusted Web sites," Adobe said in its advisory.
A series of recent vulnerabilities affecting Adobe's software -- clickjacking and the JBIG2 vulnerability, to name a few -- have led security experts to question Adobe's approach to security.
In December, Peleus Uhley, senior security researcher on Adobe's secure software Engineering team, published a blog post titled, "We Care," to reassure security researchers that Adobe wants to work with them and to acknowledge "that Adobe needed to do more to reach out to security community and be transparent in our efforts to protect customers."
In May, Brad Arkin, Adobe's director of product security and privacy, outlined three new Adobe security initiatives in a blog post: code hardening, incident response process improvements, and regular security updates.
Also in May, the company released Adobe Reader 9.11 to address at least one critical vulnerability. The following month, it released Reader 9.12 to fix nine critical vulnerabilities.
In a blog post in May, Andrew Storms, nCircle's director of security operations, likened Adobe's initiatives to the approach Microsoft took a decade ago when security issues threatened its reputation. He said that Adobe is off to a great start in rehabilitating its image and that it still had a long way to go.
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