» Topic:  Anti-Virus Protection for WMF Flaw Still Inconsistent

» Added by:  Larry Seltzer

» Date:  1.1.2006

  Days after the revelation of a flaw in Windows' handling of WMF graphics files, dozens of exploits are being spread from thousands of adware sites. But good protection is available.

At the same time, further testing confirms that a workaround issued by third parties and endorsed by Microsoft Corp. is effective in most regards, and in the most important circumstances, but not in all. Also, the workaround has side effects that could prove troublesome.

AV-Test, which tests anti-malware products, has been tracking the situation closely and has, so far, analyzed 73 variants of malicious WMF files. Products from the following companies have identified all 73:

* Alwil Software (Avast)
* Softwin (BitDefender)
* ClamAV
* F-Secure Inc.
* Fortinet Inc.
* McAfee Inc.
* ESET (Nod32)
* Panda Software
* Sophos Plc
* Symantec Corp.
* Trend Micro Inc.
* VirusBuster

These products detected fewer variants:

* 62 — eTrust-VET
* 62 — QuickHeal
* 61 — AntiVir
* 61 — Dr Web
* 61 — Kaspersky
* 60 — AVG
* 19 — Command
* 19 — F-Prot
* 11 — Ewido
* 7 — eSafe
* 7 — eTrust-INO
* 6 — Ikarus
* 6 — VBA32
* 0 — Norman

The difference for the more effective products is likely to be heuristic detection, tracking the threat by identifying the basic techniques of the exploit, rather than looking for specific patterns for specific exploits.

The latter technique leaves users vulnerable to threats that the vendor has not yet identified and protected against. Mikko Hypponen of F-Secure, when asked about the matter, said, "Heuristic detection rocks."

After some concern was expressed about the efficacy of the workaround proposed by third parties and endorsed by Microsoft, it appears that it is basically effective at preventing exploitation in the most common circumstances, but not in all.

Source: eweek.com