Bangalore,September 16 2015: Security  specialists  have alerted   enterprises  to cyber attacks that are targeting  routers made by CISCO.  India is in the short list of  four countries  where routers have been known to come implanted with malicious software called SYNful Knock,  which can  help Net baddies  scoop up all and any of the data  traffic  passing through the routers. 
The alert came from a top US-based  Net  security specialist -- FireEye--   which  published a blog yesterday, on the subject which said: "A  router implanted with a backdoor provides attackers a very easy entry point to establish a foothold and compromise other hosts and critical data.... While this attack could be possible on any router technology, in this case, the targeted victims were Cisco routers. The Mandiant* team found 14 instances of this router implant, dubbed SYNful Knock, across four countries: Ukraine, Philippines, Mexico, and India.... We believe that the detection of SYNful Knock is just the tip of the iceberg when it comes to attacks utilizing modified router images (regardless of vendor). As attackers focus their efforts on gaining persistent access, it is likely that other undetected variants of this implant are being deployed throughout the globe. (*Mandiant,is  a FireEye company, provides incident response and security assessment services) 
In August 2015,  Cisco had issued an alert  or   Security Activity Bulletin about this type of attack.
This is not the first instance of Cisco routers being targeted:  In Glenn Greenwald's 2014 book " No Place to Hide" ( Hamish Hamilton, Rs 599)  he  reproduces  material  provided by US  National Security Agency  whistle blower  Edward Snowden that show that  murky US agencies were intercepting  shipments of networking hardware from Cisco to  insert spy hardware." “We simply cannot operate this way"  CISCO Chairman John Chambers  protested to President Obama.  The book includes a slide (on page 149 of the book)  which  purportedly shows  operatives  intercepting a Cisco consignment.
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