Criminals borrowing HTTPS security to hide attacks, Dell Security finds

The secure HTTPS protocol might not be the protection it once was according to IT giant Dell which has spotted an increase in the number of attacks trying to sneak malware past firewalls using the same technique.

Dell Security calculates using traffic sensors built into the SonicWALL infrastructure that feeds into its Global Response Intelligence Defense (GRID) that the number of HTTPS web connections in use rose from 182 billion in January 2014 to 437 billion by March 2015,

This means that HTTPS made up the majority of web connections, averaging around 60 percent throughout the year. Although this is only one company's numbers, it's clear that the adoption of SSL/TLS by many large brands shows how encrypted web traffic has become almost a default for many sites.

Unfortunately, criminals also cottoned on to the idea too, launching more attacks exploiting the same technology. One noted by Dell was Yahoo's struggle with malvertising launched from its web pages - because it was encrypted would have been able to circumvent controls on any firewall lacking SSL inspection.

Dell also mentions the more recent Forbes incident in which Chinese hackers hosted malware on the news outlet's 'Thought of the Day' page to infect specific types of visitors by directing visitors to a Flash zero day exploit (although we were unable to confirm that the site was using HTTPS).

Regardless, wihle many firewalls will have SSL inspection but some won't. Home users - including home workers - operating though basic gateways would be wide open to this type of attack unless routed via a company VPN.

"Managing threats against encrypted web traffic is complicated," said Dell Security's executive director, Patrick Sweeney.

"Just as encryption can protect sensitive financial or personal information on the web, it unfortunately can also be used by hackers to protect malware. One way organisations mitigate this risk is through SSL-based web browser restrictions, with exceptions for commonly used business applications to avoid slowing company productivity."

Beyond HTTPS, the firm detected more point-of-sale (POS) attacks, with the firm's researchers isolating 13 malware types during the year compared to 2013's three. The attacks also got better than before with new techniques such as memory scraping and, of course, the sort of encrypted exfiltration referenced by HTTPS.

Global SCADA incidents rose from 91,676 in January 2012 to 675,186 in January 2014, including 202,322 in Finland, 69,656 in the UK, and 51,258 in the US, a prevalence Dell puts down to the number of Internet-connected systems in these countries.

"Everyone knows the threats are real and the consequences are dire, so we can no longer blame lack of awareness for the attacks that succeed," Sweeney.

"Hacks and attacks continue to occur, not because companies aren't taking security measures, but because they aren't taking the right ones."