Microsoft has taken the unusual step of issuing a workaround for a new security bug involving Microsoft Office a day before its regular Patch Tuesday update.
Hacking attacks targeting a vulnerability in the Snapshot Viewer ActiveX control for Microsoft Access prompted Redmond's security gnomes to issue an advisory on Monday. The flaw affects the Snapshot Viewer in Microsoft Office Access 2000, 2002 and 2003. Snapshot Viewer displays summaries of Microsoft Office Access reports without requiring Access itself to be run.
Redmond said the flaw has become the focus of targeted attacks. Attack scenarios involve tricking users into visiting sites containing rogue ActiveX controls designed to exploit the vulnerability. If successful the approach would allow hackers to obtain the same rights as logged-on users to compromised machines.
Although Microsoft has not yet corrected the underlying vulnerability, it has several suggestions* on how to set a kill bit to disable an unwanted ActiveX control. Some of these involve preventing COM objects from running in Internet Explorer, or disabling scripting. The first of these means using the Registry Editor, where mistakes can really screw up your system, while the second might leave users unable to use many websites normally. Given these choices, less technically knowledgeable Windows users might do better to use either Firefox or Opera pending the availability of a patch, which Microsoft has begun to develop.
ActiveX controls are a perennial source of security problems which Microsoft plans to finally address in the bundle of security enhancements due to ship with IE8. The list of problems with the technology (frankly too long and painful to list here) goes back to the genesis of Internet Explorer or, to put it another way, a time when Billie Piper was best known as a companion of Chris Evans, rather than Doctor Who. ®
* Any time we see an advisory with three or four suggested workarounds instead of one, we can't help but think none of them work particularly well.