• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Tech

Cisco routers attacked by hackers in four countries

By
Reuters
Reuters
Down Arrow Button Icon
By
Reuters
Reuters
Down Arrow Button Icon
September 15, 2015, 10:36 AM ET
A 10801
A 10801Courtesy of Cisco

Security researchers say they have uncovered clandestine attacks across three continents on the routers that direct traffic around the Internet, potentially allowing suspected cyberspies to harvest vast amounts of data while going undetected.

In the attacks, a highly sophisticated form of malicious software, dubbed SYNful Knock, has been implanted in routers made by Cisco (CSCO), the world’s top supplier, U.S. security research firm FireEye said on Tuesday.

Routers are attractive to hackers because they operate outside the perimeter of firewalls, anti-virus, behavioral detection software and other security tools that organizations use to safeguard data traffic. Until now, they were considered vulnerable to sustained denial-of-service attacks using barrages of millions of packets of data, but not outright takeover.

“If you own (seize control of) the router, you own the data of all the companies and government organizations that sit behind that router,” FireEye Chief Executive Dave DeWalt told Reuters of his company’s discovery.

“This is the ultimate spying tool, the ultimate corporate espionage tool, the ultimate cybercrime tool,” DeWalt said.

The attacks have hit multiple industries and government agencies, he said.

Cisco confirmed it had alerted customers to the attacks in August and said they were not due to any vulnerability in its own software. Instead, the attackers stole valid network administration credentials from targeted organizations or managed to gain for themselves physical access to the routers.

“We’ve shared guidance on how customers can harden their network, and prevent, detect and remediate this type of attack,” Cisco said in a statement.

Cyberspies seen responsible
Altogether FireEye’s computer forensic arm Mandiant has so far found 14 instances of the router implants in India, Mexico, Philippines and Ukraine, the company said in a blog post. It added that this may be just the tip of the iceberg in terms of yet-to-be-discovered attacks.

Because the attacks actually replace the basic software controlling the routers, infections persist when devices are shut off and restarted. If found to be infected, FireEye said basic software used to control those routers would have to be re-imaged, a time-consuming task for technicians.

Hitherto, infections of commercial routers, while not unknown, have largely remained theoretical threats, DeWalt said, as distinct from routers consumers use at home, which according to media reports have been hit by malware in recent years.

Experts reckon there are only a small number of nations with cyber intelligence services which are capable of such attacks on network equipment, including those of Britain, China, Israel, Russia, and the United States.

“That feat is only able to be obtained by a handful of nation-state actors,” DeWalt said, while declining to name which countries he suspected might be behind the Cisco router attacks.

The malicious program has been nicknamed “SYNful” in reference to how the implanted software can jump from router to router using the device’s syndication functions.

Network logs from infected routers suggest the attacks have been taking place for at least a year, FireEye’s CEO said.

The implanted software, which duplicates normal router functions, could also potentially affect routers from other makers, DeWalt said.

Infected hardware devices include Cisco routers 1841, 2811 and 3825, FireEye said. Cisco had discontinued selling the products but still supports customers using them.

FireEye said it was only announcing its discovery after working with Cisco to quietly notify governments and affected parties. “We thought it was best to release this so everyone can fix their routers as fast as possible,” DeWalt said.

About the Author
By Reuters
See full bioRight Arrow Button Icon

Latest in Tech

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
  • Group Subscriptions
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in Tech

lancaster
AIschools
Two private school boys get probation for using AI to create 350 fake nudes of their classmates
By Mark Scolforo and The Associated PressMarch 25, 2026
7 hours ago
melania
PoliticsWhite House
Enter Melania Trump, escorted by humanoid robot: ‘I’m Figure 03, a humanoid built for the United States of America’
By Darlene Superville and The Associated PressMarch 25, 2026
7 hours ago
bernie
AICongress
Bernie Sanders and AOC launch bill to ban new data-center construction
By Matthew Daly and The Associated PressMarch 25, 2026
7 hours ago
Big TechSocial Media
A court just ruled that tech addiction is real—and dangerous. It could be Meta and YouTube’s Big Tobacco moment
By Kristin StollerMarch 25, 2026
8 hours ago
Warner gestures
AIAmerican Politics
New college grad unemployment will spike to 35% in 2 years, senator warns, forcing ‘Dario, Sam’ to quit AI fear-mongering
By Jacqueline MunisMarch 25, 2026
10 hours ago
Big TechMeta
Meta and YouTube found liable in landmark child social media harm case, ordered to pay $3 million—with punitive damages still to come
By Kaitlyn Huamani, Barbara Ortutay and The Associated PressMarch 25, 2026
10 hours ago

Most Popular

Magazine
The youngest-ever female CEO of a Fortune 500 company is fighting Trump's cuts to keep Medicaid strong
By Fortune EditorsMarch 24, 2026
2 days ago
Commentary
The Treasury just declared the U.S. insolvent. The media missed it
By Fortune EditorsMarch 23, 2026
3 days ago
Success
Palantir’s billionaire CEO says only two kinds of people will succeed in the AI era: trade workers — ‘or you’re neurodivergent’
By Fortune EditorsMarch 24, 2026
2 days ago
Success
The job market is so bad that ‘reverse recruiters’ are charging $1,500 a month just to help people look for jobs
By Fortune EditorsMarch 25, 2026
20 hours ago
Success
JPMorgan’s Jamie Dimon says remote work breeds ‘rope-a-dope politics’ and stunts young workers’ growth
By Fortune EditorsMarch 25, 2026
13 hours ago
Success
JPMorgan has started monitoring the keystrokes, video calls, and meetings of its junior investment bankers—and they say it's for employee well-being
By Fortune EditorsMarch 24, 2026
2 days ago

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.