The operation was "to support espionage, extract intellectual property, maintain persistent access to victim networks and potentially lay a foundation for future offensive operations", Washington and London said in a joint statement.
"We have high confidence Russian Federation has carried out a coordinated campaign to gain access to enterprise, small office/home office routers known as SOHO routers, and residential routers, and the switches and connectors worldwide", Joyce said in a conference call.
According to Martin, numerous techniques used by Russian Federation, "exploit basic weaknesses in network systems".
Hacked devices ranged from small home routers to ISP-grade routers and firewalls, with attackers trying to hoard as many systems as possible. For owners, they're asked to ensure network devices are up-to-date, change default passwords, and ensure the firmware on the device is from a trusted source.
The U.S. and British governments on Monday accused Russian Federation of conducting a massive campaign to compromise computer routers and firewalls around the world - from home offices to Internet providers - for espionage and possibly sabotage purposes.
"We expect the British government to declare the same". Finally, the alert outlined what erratic hardware behavior should indicate a device has been compromised. Part of the alert calls on people to step up their own security, with Manfra pointing out that the DHS can't "protect every single device".More news: Ian Somerhalder to Star in Netflix Vampire Drama Series 'V-Wars'
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Ciaran Martin, head of the UK's NCSC, said the issuing of the alert marked a "significant moment" as the two powers had never before given joint advice on how to deal with attacks.
"The NCSC is leading the way globally to issue advice and automate defences at scale to remove those basic attacks, thereby allowing us to focus on the most potent threats".
"The UK government will continue to work with the United States, other global allies and industry partners to expose Russia's unacceptable cyber behaviour, so they are held accountable for their actions", Martin added.
The unusual public warning from the White House, U.S. agencies and Britain's National Cyber Security Center results from monitoring the threat dating back more than a year.
"The attribution of this malicious activity sends a clear message to Russian Federation - we know what you are doing and you will not succeed", said a spokesperson for the United Kingdom government.
No sanctions or penalties were announced Monday, and the alert is unrelated to expected sanctions on Russian Federation in coming days, though Joyce reiterated that "all elements of U.S. power are available to push back" on such hacking efforts. "The UK and USA have separately and together already called out bad behavior by Russian Federation in cyberspace, but never before have we joined together to give the same advice to our industry and citizens".