Adobe patches critical Flash bugs, ships sandboxed plug-in for Firefox
Adobe on Friday patched seven critical vulnerabilities in Flash Player—the fifth security update so far in 2012—and released a sandboxed plug-in for Mozilla’s Firefox.
The company also released the “silent update” tool for OS X, and said it had prepped Flash for the upcoming OS X 10.8, aka Mountain Lion, by signing its code, a requirement if users are to install software downloaded from sources other than Apple’s own Mac App Store.
“These updates address vulnerabilities that could cause a crash and potentially allow an attacker to take control of the affected system,” said Adobe in an advisory published Friday.
The flaws were all over the map, and included memory corruption, integer and stack overflow, and security bypass bugs. One of the seven was tagged as a “binary planting” vulnerability in the Flash installer.
“Binary planting” is a synonym for what others call “DLL load hijacking,” a bug class first uncovered nearly two years ago by HD Moore, chief security officer at Rapid7 and creator of the open-source Metasploit penetration-testing toolkit.
Because many Windows applications don’t call DLLs using a full path name, instead using only the filename, hackers can trick an application into loading a malicious file with the same title as a required DLL.
Unlike the last Flash security update, which Adobe issued May 4, Friday’s bug patches are for vulnerabilities that the company has not seen exploited in the wild.
Among those Adobe credited for reporting the vulnerabilities was a researcher from the Google Chrome team, another from Symantec and two engineers who work for Microsoft.
Microsoft and Adobe have been working even closer than usual of late: Last week, Microsoft announced that it had, with Adobe’s help, integrated Flash Player into the Metro version of Internet Explorer 10 (IE10).
That move seemed to contradict Microsoft’s earlier promise that it would not allow plug-ins—Flash Player is probably the most widely-used browser plug-in on the planet—in IE10 on Metro, the new tablet-oriented user interface (UI) within Windows 8 and the sole mode on Windows RT.
Also included in Flash Player 11.3 was a sandboxed plug-in for Firefox and the promised silent update tool for OS X users.
Adobe first talked about sandboxing Flash for Firefox in February, when it released a beta version of the plug-in for that browser on Windows Vista and Windows 7.
A sandbox isolates processes on the computer, preventing, or at least hindering, hackers trying to exploit an unpatched vulnerability, escalate privileges and push malware onto the machine.
Adobe first sandboxed Flash Player for Google’s Chrome in late 2010 after working with Google engineers; the sandboxed plug-in for Firefox came after similar cooperation from Mozilla engineers, Adobe said several months ago.
The Mac background updater debuted just over a month ago in a beta version of Flash Player 11.3, but went final Friday. The tool is identical to the Windows version, which Adobe launched in March: It pings Adobe’s servers every hour until it gets a response. If it reaches Adobe and finds no ready update, the tool re-checks the servers 24 hours later. Found updates, however, are applied entirely in the background, and do not display notices on the screen or require the user to take any action.
By default, Flash 11.3 has silent updates switched on for OS X users, but they can change the setting to continue to receive on-screen alerts, or more dangerously, decline all updates.
Adobe has also prepared Flash Player for the release of Apple’s next desktop operating system, Mountain Lion.
Mountain Lion includes a new feature called Gatekeeper that by default will let users install only software downloaded from the Mac App Store — the Apple-curated market that debuted in January 2011—or signed with certificates Apple provides free-of-charge to registered developers.
Gatekeeper is Apple’s reaction to last year’s spread of the Mac Defender malware, which was tucked into fake security software: Gatekeeper will prevent such “scareware” from ending up on Macs.
“Starting with Flash Player 11.3, Adobe has started signing releases for Mac OS X using an Apple Developer ID certificate,” said Brad Arkin, Adobe’s senior director of security, products and services, on a company blog today. “Therefore, if the Gatekeeper setting is set to ‘Mac App Store and identified developers,’ end-users will be able to install Flash Player without being blocked.”
Because Flash is not distributed through Apple’s desktop app market, if users set Gatekeeper to the most restrictive option—“Mac App Store”—they won’t be able to install or update Flash Player.
Flash Player was upgraded Friday to version 11.3 for Windows and OS X, to 11.2 for Linux and to 11.1 for Android. As of 3 p.m. ET, Google had yet to update Chrome, which includes its own version of Flash, to gives its users the patched edition.