Aug 12, 2010 14:58 GMT  ·  By

Symantec reports that spam accounted for almost 92 percent of all email traffic last month, while the number of emails with malicious attachments has decreased compared to June.

Spam output has again passed the ninety percent mark in July, with junk emails representing 91.98% of the total traffic, compared to 88.32% in June.

Another noteworthy change has been observed in the size of spam emails, specifically in the over 10 KB range, where the score plummeted from 21.78% to 12.32%.

"This is partly attributed to a decrease in spam containing malware attachments," Symantec researchers note in the company's latest State of Spam & Phishing report (PDF).

Internet services remains the leading spam category, accounting for of 33% of junk emails, while pharmacy spam has spiked in July, putting the health category in second place with 21%. Financial and product spam comes next with 13%.

As far as origin goes, 22% of all spam traffic originated from the United States, putting the country way ahead in front of its next competitors, India and the Netherlands, both with 6%.

United Kingdom (5%), Brazil (5%), Germany (4%), France (3%), Italy (3%), Vietnam (3%) and Romania (2%) complete the top ten. The only significant change compared to last month is Vietnam appearing in the list.

As far as spam URL TLD distribution is concerned .com is obviously leading, but it has added almost six percent to its score and is now situated at 59.1%.

The use of links to .ru domains in spam has decreased by 7.5% and is now 22.0%, .org remained constant at 6.1% and .net has made a surprising appearance in the top five list for July, with a 2.2% percentage.

"Since the World Cup ended in mid-July, spammers have shifted their attention to other current events and news," like the BP oil spill, Symantec also notes in its report.

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