Broadband modems using Intel's bungled Puma 6 chipset can be overloaded and virtually knocked offline by a trivial stream of packets, it is claimed.
Effectively, if there's someone you don't like, and they are one of thousands upon thousands of people using a Puma 6-powered home gateway, and you know their IP address, you can kick them off the internet, we're told.
This week,
inquisitive netizens discovered that, when presented with even modest amounts of packets – as little as 1.5Mbps – modems equipped with a Puma 6 can be slowed to a crawl.
According to one engineer who spoke to El Reg on the issue, the flaw would be "trivial" to exploit in the wild and would effectively render the targeted box useless for the duration.
"You send a stream of 200Kbps of TCP, UDP or maybe even ICMP to different port numbers and it has a tiny table to keep track of these and become immd unresponsive. It comes back after you stop," our tipster explains.
"It can be exploited remotely and there is no way to mitigate the issue."
This will be particularly frustrating for Puma 6 modem owners because the boxes are pitched as gigabit internet modems, meaning many of the devices can potentially be slowed to a crawl simply by getting traffic flowing at a fraction of the connection speeds you are paying for.
The Puma 6 chipset is used in a number of ISP-branded cable modems, including some supplied by Comcast in the US and Virgin in the UK, where customers have already begun
filing complaints over the sluggish performance of the routers.
"Immediately following installation I noticed I was getting significant spikes in latency, resulting in unstable connections on VPN, and poor gaming/streaming performance," writes one customer who's asking for a replacement.
The reports are yet another nail in the coffin of the ill-fated Puma 6 chipset. Shortly after it was released, it was
found to be prone to serious latency issues. The problem has already landed
one vendor in court on a class action lawsuit. ®
