An undersea cable laid off the coast of east Africa last year has led to a boom in spam coming from the region, according to a new study from Symantec.
A cable laid last summer boosted the broadband connectivity to countries along the country's eastern coast in July last year, Symantec noted in its May 2010 MessageLabs Intelligence Report, published on Wednesday. The consequent rise in broadband availability has given spammers access to a new source of machines for their botnets, it said.
"Historically, broadband adoption has been a tipping point for spammers to acquire more bots," said MessageLabs analyst Paul Wood, in a statement. "The new undersea fibre optic cable along the east coast of Africa has enabled rapid growth in the number of users obtaining high-speed connections to the internet, creating a great opportunity for attackers to infect new machines and create new bots."
There has been a significant rise in spam coming from Kenya, Rwanda and Uganda, Symantec said. Spam output from those east African countries has risen by 7.2, 6.3 and 5.7 times, respectively, compared with levels seen a year ago.
While the majority of African spam still originates from outside of the eastern region, the new cable boosted eastern Africa's proportion of the continent's spam to 19 percent, up from 13 percent. Meanwhile, the proportion of spam coming from the rest of Africa decreased from 86 percent to 80 percent, Symantec said.
Overall, spam originating from Africa rose by 1.2 billion junk messages per day. Africa now originates three percent of spam worldwide, up from just under two percent a year ago, according to the report.
Earlier this week, VeriSign iDefense reported that botnets are available for hire for as little as $8.94 (£6.04) per hour, emphasising how little financial muscle or technical expertise is needed to carry out attacks.
Worldwide, the Symantec study found that in May phishing scam emails accounted for one in 237.1 emails, or 0.42 percent, up 0.2 percentage points on April. Phishing emails represented 80.6 percent of all email-borne threats, up 10.3 percentage points on April.
The UK remained the country against which the most phishing attacks were directed, with one in 121.8 phishing emails aimed at British systems, Symantec said.