Microsoft Flunks Antivirus Tests. Who Aced Them?

Credit: AV-TEST

(Image credit: AV-TEST)

Every antivirus software package promises to protect your computer from danger, but when it comes to detecting malware, there are huge differences among them. German Lab AV-TEST today (Jan. 22) released the results of its latest Windows 7-based tests, and Microsoft's free Security Essentials application came in near the bottom, while paid packages from Bitdefender, Kaspersky Lab and Trend Micro were tied at the top.

It's common knowledge among computer-security professionals that Microsoft Security Essentials and its Windows 8 counterpart, Windows Defender, are terrible at detecting malware. Microsoft itself has said that the two are meant only to be stopgap solutions to confer some degree of herd immunity on Windows users who refuse to install third-party antivirus software.

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Just under the top three were Avira, best known for its free antivirus software, and Qihoo, a Chinese antivirus maker, which each scored 17 out of 18 possible points. The products by the better-known Bitdefender, Kaspersky Lab and Trend Micro got 17.5 points each. Avira actually scored better in the malware-protection category than either Bitdefender or Kaspersky; like the offering from Trend Micro, it got a perfect 6 in stopping viruses, worms, Trojans and other malware.

Twenty-eight products in all were tested on Windows 7. They were scored on how well each detected 153 pieces of newly discovered "zero-day" malware and 12,327 pieces of malware that had been discovered in the previous four weeks.

To be specific, the top three scorers were Bitdefender Internet Security, Kaspersky Internet Security and Trend Micro Internet Security, all of which have a list yearly subscription price of $60 for one user and $80 for three users, although discounts can often be found online. (Each company makes several antivirus products.) Avira Antivirus Pro is cheaper, at about $35 list for one user (it's priced in euros), while Qihoo 360 Internet Security is completely free.

Only Trend Micro was able to catch 100 percent of both kinds of malware. Avira and Kapersky snagged 99 percent of the zero-day malware, compared to the 97 percent detected by Bitdefender and Qihoo 360 (according to Qihoo, both use the same malware engine). All four blocked 100 percent of the older malware.

Slightly underperforming the top ranks were the offerings from the big American antivirus firms. McAfee Internet Security and Norton Security each scored 16.5, with the first doing slightly better on performance, the second slightly better on usability. Both scored a healthy 5.5 on protection; Norton got 99 percent of zero-day malware compared to McAfee's 93 percent, but McAfee found all the older malware samples, while Norton only got 99 percent of those.

Differences between a few percentage points in the 90s may not sound like much, but it's what's left over that really counts. A 97-percent detection rate will let three times as much malware come over the castle walls as would a 99-percent detection rate.

Tied with McAfee and Norton for third-highest score were F-Secure Internet Security, which scored a perfect 6 in malware protection yet suffered a bit in performance and usability, and Qihoo 360 Antivirus, a separate product from Qihoo 360 that's available only in China.

Rounding out the top 10 highest-scoring products was Bullguard Internet Security, which scored a solid 16 out of 18.

On the other end of the spectrum were Microsoft Security Essentials, which got zero out of 6 in the protection category (it detected only 49 percent of zero-day malware) yet still scored 11 points thanks to its ease of use and low system impact, and ThreatTrack's VIPRE Internet Security. VIPRE found 76 percent of zero-day malware, yet did poorly on performance and usability; it scored 9.5 out of 18 and came in dead last.

Paul Wagenseil is a senior editor at Tom's Guide focused on security and gaming. Follow him at @snd_wagenseilFollow Tom's Guide at @tomsguide, on Facebook and on Google+.

Paul Wagenseil

Paul Wagenseil is a senior editor at Tom's Guide focused on security and privacy. He has also been a dishwasher, fry cook, long-haul driver, code monkey and video editor. He's been rooting around in the information-security space for more than 15 years at, SecurityNewsDaily, TechNewsDaily and Tom's Guide, has presented talks at the ShmooCon, DerbyCon and BSides Las Vegas hacker conferences, shown up in random TV news spots and even moderated a panel discussion at the CEDIA home-technology conference. You can follow his rants on Twitter at @snd_wagenseil.