• Home
  • News
  • Fortune 500
  • Tech
  • Finance
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
TechFortune 500

Big Security Bug Affects Hundreds Of Thousands Of Cisco Devices

By
Jonathan Vanian
Jonathan Vanian
Down Arrow Button Icon
By
Jonathan Vanian
Jonathan Vanian
Down Arrow Button Icon
September 22, 2016, 6:24 PM ET
Cisco Announces Quarterly Earnings
SAN JOSE, CA - AUGUST 10: A bicyclist rides by a sign that is posted in front of the Cisco Systems headquarters on August 10, 2011 in San Jose, California. Cisco Systems reported better-than-expected fourth quarter revenues with a 3.3 percent rise to $11.2 billion as the company continues to scale down its business. (Photo by Justin Sullivan/Getty Images)Justin Sullivan — Getty Images

Hackers using NSA-related hacking tools could exploit a major cyber security vulnerability impacting hundreds of thousands of Cisco switches, routers, and other networking gear.

The vulnerability, disclosed by Cisco (CSCO) last week, has impacted at least 859,000 devices, according to Shadowserver Foundation, an independent cyber security group and Cisco partner that has been scanning Cisco routers and switchers worldwide.

Of those devices affected, 259,000 are located in the U.S., 44,000 are in Russia, and another 43,000 are in the U.K. Cisco said Shadowserver would share data with owners of the affected devices and related IP addresses. If customers want detailed reports, they “can contact Shadowserver and get their section of the scan results,” said a Cisco spokesperson.

Hackers who exploit the vulnerability—which affects Cisco’s popular IOS networking operating system—would be able to get access to data in the device’s memory, “which could lead to the disclosure of confidential information,” Cisco said. Cisco says its networking software is the “world’s most widely deployed.”

Get Data Sheet, Fortune’s technology newsletter.

The Cisco security post said that some Cisco customers have been compromised by the security bug, but did not say which customers or the severity of the attacks.

It said that it was alerted to the security vulnerability on August 15, but it did not say who brought the information to the company’s attention. In the post about the vulnerability, Cisco said a hacking group called “the Shadow Brokers” had posted details online of how to exploit an older Cisco product.

In mid-August, the Shadow Brokers claimed responsibility for posting online a collection of tools and exploits created by another organization, “the Equation Group,” which many analysts have linked to the NSA.

The leaked materials included documentation about how to crack into data center gear built by companies like Cisco, Juniper Networks (JNPR), Fortinet, and a Chinese networking company Topsec. The Shadow Brokers said at the time that it would auction the exploits to the highest bidder.

Cisco then investigated and learned that other products, like its popular networking software, could be affected by the same exploit. The networking software works with several of Cisco switches and routers.

Cisco said there is no way to fix the problem until it creates a patch, which it said will be available in the coming days. However, it said that companies can take some “countermeasures” in the meantime.

For more about Cisco, watch:

The company advises information technology administrators to use network-monitoring tools to scan their networks for strange activity that could tip them off of possible hacking attempts. Cisco also posted a technical guide for network admins to follow that will help them determine if their devices are vulnerable as well as an incident report page.

A Cisco spokesperson said the company is unable to “speculate about who may try to exploit this vulnerability or why they would do so.”

About the Author
By Jonathan Vanian
LinkedIn iconTwitter icon

Jonathan Vanian is a former Fortune reporter. He covered business technology, cybersecurity, artificial intelligence, data privacy, and other topics.

See full bioRight Arrow Button Icon

Latest in Tech

Future of WorkJamie Dimon
Jamie Dimon says even though AI will eliminate some jobs ‘maybe one day we’ll be working less hard but having wonderful lives’
By Jason MaDecember 7, 2025
4 hours ago
CryptoCryptocurrency
So much of crypto is not even real—but that’s starting to change
By Pete Najarian and Joe BruzzesiDecember 7, 2025
9 hours ago
Elon Musk
Big TechSpaceX
SpaceX to offer insider shares at record-setting $800 billion valuation
By Edward Ludlow, Loren Grush, Lizette Chapman, Eric Johnson and BloombergDecember 6, 2025
23 hours ago
Big TechApple
Apple rocked by executive departures, with chip chief at risk of leaving next
By Mark Gurman and BloombergDecember 6, 2025
1 day ago
Nvidia CEO Jensen Huang said China is better equipped for an AI data center buildout than the U.S.
AITech
Nvidia CEO says data centers take about 3 years to construct in the U.S., while in China ‘they can build a hospital in a weekend’
By Nino PaoliDecember 6, 2025
1 day ago
Arts & EntertainmentMedia
Former Amazon Studios boss warns the Netflix-Warner Bros. deal will make Hollywood ‘a system that circles a single sun’
By Jason MaDecember 6, 2025
1 day ago

Most Popular

placeholder alt text
AI
Nvidia CEO says data centers take about 3 years to construct in the U.S., while in China 'they can build a hospital in a weekend'
By Nino PaoliDecember 6, 2025
1 day ago
placeholder alt text
Economy
The most likely solution to the U.S. debt crisis is severe austerity triggered by a fiscal calamity, former White House economic adviser says
By Jason MaDecember 6, 2025
23 hours ago
placeholder alt text
Real Estate
The 'Great Housing Reset' is coming: Income growth will outpace home-price growth in 2026, Redfin forecasts
By Nino PaoliDecember 6, 2025
1 day ago
placeholder alt text
Asia
Despite their ‘no limits’ friendship, Russia is paying a nearly 90% markup on sanctioned goods from China—compared with 9% from other countries
By Jason MaNovember 29, 2025
8 days ago
placeholder alt text
Big Tech
Mark Zuckerberg rebranded Facebook for the metaverse. Four years and $70 billion in losses later, he’s moving on
By Eva RoytburgDecember 5, 2025
2 days ago
placeholder alt text
Economy
JPMorgan CEO Jamie Dimon says Europe has a 'real problem’
By Katherine Chiglinsky and BloombergDecember 6, 2025
22 hours ago
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
  • Leadership
  • Success
  • Tech
  • Asia
  • Europe
  • Environment
  • Fortune Crypto
  • Health
  • Retail
  • Lifestyle
  • Politics
  • Newsletters
  • Magazine
  • Features
  • Commentary
  • Mpw
  • CEO Initiative
  • Conferences
  • Personal Finance
  • 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
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map

© 2025 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.