The US, which was topped the list in spam relaying during the same period a year ago, now relays one in 15 of all spam emails.
The UK has returned to the list of 12 top spam senders during the quarter after remaining out of the list of spam-relaying countries for the last four consecutive quarters.
Sophos senior technology consultant Graham Cluley said spam emails arrive in the inbox via other people’s infected computers.
"The latest Dirty Dozen report suggests that a not insignificant number of PCs in India are harbouring malware infections that turn PCs into spam-spitting zombie slaves, controlled by the cybercriminals who make money by punting junk emails to promote questionable goods, or simply use malicious spam to infect more computers," Cluley said.
"The authorities in India need to make IT security education a priority."
"One would be safe to assume that, if computer users in the country are being targeted in order to relay spam, they are likely victims of other online threats such as fraud."
Saudi Arabia is the new entrant to the list of top spam senders during the quarter, relaying 5.1% of spam for the period.
Sophos said the rise in spam from the country could be due to the Festi botnet which infected many computers there in August.
Other new entrants since last quarter are Turkey and Germany, while Pakistan, Russia, Poland and Thailand are not there in the list during this quarter, who were earlier there.
"Spam is still a big threat to computer users, particularly for those who might not be aware of the simple dangers of clicking on links in unsolicited emails," Cluley added.
"This could represent a ticking time bomb as Asian nations like India and China – which actually have comparatively few computer users in terms of their overall populations – continue to become more connected."
This article is from the CBROnline archive: some formatting and images may not be present.
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