German independent security firm AV-Test has released evaluations of security software for Windows 8 for the first time, and – not entirely surprisingly – it once again found Microsoft's own products were among the weaker performers.

The firm tested its usual batch of 25 antivirus products for consumers, plus eight aimed at corporate users, during the first two months of 2013. It published its results on Saturday.

Microsoft Windows Defender – the rebadged version of Microsoft Security Essentials that comes bundled with Windows 8 – scored just 2.0 out of 6 in AV-Test's Protection rankings. Redmond's enterprise-oriented System Center Endpoint Protection scored a paltry 1.5.

According to AV-Test, Windows Defender managed to spot just 82 per cent of zero-day malware attacks during January and 81 per cent during February, based on 125 samples. The industry average was 95 per cent.

Windows Defender did a little better at detecting "widespread and prevalent" malware, catching 98 per cent of samples thrown at it in January and 99 per cent in February. But that still wasn't quite as good as the industry average, which was 99 per cent.

On the enterprise side, System Center Endpoint Protection caught a consistent 98 per cent of widespread malware samples across both months. That was another subpar showing, though, given that on average, the other enterprise products identified all the samples.

And Endpoint Protection's track record for zero-day malware was even worse than Windows Defender's, spotting just 80 per cent of the samples in January and 83 per cent in February.

Both of Microsoft's products ranked fairly well in other aspects AV-Test looked at. In particular, both scored 6 out of 6 for Usability, with no false positives spotted and no legitimate actions being blocked erroneously. Both offered reasonably good performance as well, although here Endpoint Protection had the edge over Windows Defender.

Many customers might argue, however, that high usability and fast performance aren't much good when the product isn't so hot at what it purports to do: stopping malware.

But others are likely to disagree with AV-Test's assessment of Redmond's security products – not least of which is Microsoft itself. AV-Test has butted heads with the software giant over its testing methodology in the past, which Microsoft says uses malware samples that "don't represent what our customers encounter."

Be that as it may, several other products significantly outperformed Microsoft's on the Protection portion of this round of AV-Test's evaluations. Leading the pack in the consumer sector were products from F-Secure, G Data, Bitdefender, Kaspersky, BullGuard, and Trend Micro, all of which earned perfect scores. Kaspersky and F-Secure topped the list of the enterprise products.

The full results of AV-Test's January-February testing can be found on the company's website. ®