For the second time in two days, Adobe Systems has warned users of multiple vulnerabilities in one of its most-popular programs and issued a security update to plug the holes.
Wednesday's update was the fourth patch job on the ubiquitous Flash Player this year, and followed by one day an even larger collection of fixes for Adobe Reader, the Web's default PDF (Portable Document Format) application.
The Flash Player update addressed six bugs in version 18.104.22.168 that run the range from cross-site scripting and information disclosure vulnerabilities to flaws that could be used to inject malicious HTML code in Web sites and launch "DNS rebinding" attacks.
Adobe first quashed DNS rebinding bugs in Flash in December 2007; the latest fix again credited researchers from Stanford University and the University of California for reporting the flaw. DSN rebinding vulnerabilities, which make up a subset of cross-site scripting bugs, can let hackers circumvent firewalls and launch large-scale IP address hijacking attacks.
Another flaw fixed in the update also has a long history. "This update prevents an issue with the Flash Player interpretation of jar: protocol on Mozilla browsers that could potentially lead to information disclosure," Adobe said in one of the accompanying advisory's terse descriptions. Mozilla patched its Firefox browser nearly a year ago to crush a pair of bugs associated with the "jar:" protocol handler. At the time, the move was notable because Mozilla had let a fix languish for nine months.
Wednesday's update brought the older version of Flash to version 22.214.171.124. Users running the newer Flash Player 10 do not need to update their software.
Users can check which version of Flash Player they currently have installed by visiting this page on the Adobe site.
Adobe last patched Flash on October 15, when it unveiled version 10.