Friday, April 24, 2009

Windows XP and Adobe Flash Controls

There's a version issue with the latest XP SP - Service Pack 3 - when it comes to Adobe Flash controls. OK, I just had a rethink and I'll post the whole entry that Stefan Kanthak sent to Bugtraq as it is an interesting read. The issue he posts is definitely a valid one and one that you will need to keep an eye on for your XP clients...

Windows Update (as well as Microsoft Update and the Automatic Update) installs an outdated (and from its manufacturer unsupported) Flash Player ActiveX control on Windows XP.

Although this fact is nothing really new it but shows the lack of taking care for security problems and in general the chuzpe of many software "producers" to ship their "products" with outdated and often vulnerable components.

The ouverture:

* Windows XP RTM (i.e. the original release version without any service packs) installs a Flash Player ActiveX control SWFLASH.OCX v5.0r42

* Windows XP Service Pack 1 updates the SWFLASH.OCX to v5.0r44

* Windows XP Service Pack 2 (released in August 2004) replaces the SWFLASH.OCX with FLASH.OCX v6.0r79

* security update KB913433 (see <>
and <>)
updates FLASH.OCX to 6.0r84

* security update KB923789 (see <> and <>)
updates FLASH.OCX to 6.0r88

* Windows XP Service Pack 3 (released in April 2008) contains the same FLASH.OCX v6.0r79 as Service Pack 2, i.e. none of the security updates published after Service Pack 2 were incorporated!
The MSKB article KB948460 but STILL states wrong that KB913433 (sic!) is included in Service Pack 3

To my knowledge Adobe stopped direct support for Flash Player 6 in late 2005, the newest version of Flash Player ActiveX 6.0 available on their web site <> is 6.0r79 from 2005-11-11. Later versions of Flash Player ActiveX 6.0 were available from Microsoft only: <>
and <>

I doubt that these outdated Flash Player ActiveX controls are safe and not vulnerable to current exploits, so Microsoft puts it's customers clearly at risk.

The unhappy end:

* Start with a fully patched Windows XP with Service Pack 3 AND the current Adobe Flash Player ActiveX v10.0r22.87 installed.

Since recent Flash Player installers remove any older versions of the ActiveX control this means that neither FLASH.OCX nor SWFLASH.OCX are present in
%SystemRoot%\System32\Macromed\ or

* Install an arbitrary software product that installs a Flash Player ActiveX prior to 6.0r88 (there are MANY software products that do so).

For example, get the current MSN CD-ROM "MSN 9.6-PROD", part no. X14-85160-02 DE from Microsoft; this CD-ROM contains the product "Digital Image Standard Edition 2006" v11.1 from 2007-01-29, which installs an outdated and VULNERABLE FLASH.OCX v6.0r29 to

Note that the installer was created AFTER KB923789, which but was not incorporated. Does Microsoft really care about security?

If you dont want to order the MSN CD-ROM a trial version of "Digital Image Starter Edition 2006" is available from

If you dont want to install such a big product either, get the Windows Update KB913433 from
extract the Flash Player ActiveX installer INSTALL_FP6_WU.EXE from the package and run the installer.

The attempt to install a Flash Player ActiveX prior to 6.0r88 over a later version does not YET any harm, since starting with 6.0r88 Adobe sets deny ACLs on the
%SystemRoot%\System32\Macromed\Flash\FLASH*.OCX as well as all the registry entries which prevent earlier Flash Player ActiveX installers to overwrite them, so any Flash Player ActiveX 6.0r88 and later is preserved.

Any of the above mentioned products but installs the previously not existent file

* Visit <> (or wait till the daily run of the Automatic Update) and install the Windows Update KB923789.

This but DOES harm: since the Flash Player ActiveX installer that has been wrapped in KB923789 (re-)sets the ACLs it overwrites the registry entries of the newer/recent Flash Player ActiveX. DAMAGE DONE!

I informed Microsoft in the last two years several times about this problem and discussed it with various members of their Microsoft Security Response Center, but the problem persists.


The Outspoken Wookie

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