Feb 23, 2011 10:04 GMT  ·  By

German antivirus vendor Avira warns that the number of phishing attacks is again on the rise after a significant decline in December.

"While the numbers for Phishing in December were almost all red, showing a dramatic drop for the .org (-151%), .com(-76%) and .net(-24%) domains, we now have seen the exact opposite development in January 2011.

"Phishing was definitely on the rise and even if the malware URLs still show mostly as red numbers, some of them have also increased," says Sorin Mustaca, data security expert at Avira.

PayPal remains the most phished brand on the Internet, having been targeted in almost 37% of attacks last month, an increase of 52.68% since December.

It's owner, eBay, was also among the favorite phishing targets, with attacks against the website almost doubling since December and accounting for 27% of the total.

Facebook (4.68%), Yahoo! (3.46%), Chase Bank (2.43%), Visa (1.82%), Commonwealth Bank (1.67%), Banco Santander (1.43%) and World of Warcraft (1.35%) complete the top 10.

As far malware URL extensions go, .txt managed to stay at the top with 38.03% and was followed by .exe with 18.18%, .jpg with 5.65%, .php with 4.13% and .zip with 2.19%.

All of these, except .zip, registered a decline last month. The biggest increase was registered by .ocx, a file type associated with Microsoft's Object Linking and Embedding (OLE) Control Extension.

"These files can become infected and it are quite hard to detect as they are usually loaded by other modules," explains Mr. Mustaca.

The fact that the beginning of January was marked by a steep decline in spam traffic was reflected in Avira's statistics. Nevertheless, the pharmaceutical category managed to stay at the top.