Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Attacks/Breaches

1/7/2010
05:53 PM
Connect Directly
Twitter
RSS
E-Mail
50%
50%

Critical Juniper Router Flaw Triggers Prompt Patching

Vulnerability causes routers to crash and reboot

Juniper Networks yesterday issued a patch for a serious and exploitable flaw in its router operating system that could cause a router to crash altogether.

The critical security alert issued to Juniper customers and partners set off a rare flurry of router-patching last night, security experts say. "It's not atypical to not apply low-criticality patches to core routers. Now that this has been classified as 'critical,' people seem to be reacting," says Daniel Kennedy, a partner with Praetorian Security Group, which has been studying the vulnerability and says it heard many ISPs were already applying the patches last night.

Organizations don't routinely patch routers; they typically don't have the resources to do so, nor is patching a router as high a priority as patching a server, for instance. Some avoid patching because a major breach is less likely than the possibility of an unintentional outage from applying a router update.

And many organizations incorrectly assume their customized router configurations aren't as big of a target. But security experts -- such as Felix "FX" Lindner, who has conducted groundbreaking research on Cisco router vulnerabilities -- have demonstrated that exploiting routers isn't as hard as was once thought.

Dan Kaminksy, director of penetration testing for IOActive, says this Juniper vulnerability should be patched--and fast: "A remote kernel panic on most versions of the second most popular routing platform on the Internet is significant. IT admins should take this threat to their infrastructure seriously, and patch immediately," Kaminsky says.

There has been no sign of an active exploit for the Juniper router vulnerability yet, but the attack works like this: When the router receives a TCP header with a crafted options field, JUNOS, Juniper's router operating system kernel, crashes and the OS reboots. JUNOS' firewall filter is unable to filter the packet, either. Juniper's JUNOS versions 3, 4, 5, 6, 7, 8, and 9 series routers are all affected by the flaw, which basically results in a denial-of-service attack.

"So JUNOS versions released after January are reported to crash upon receiving a TCP packet that ACL filtering will not stop. Per Juniper, there is no real effective workaround, just application of the provided patch," Kennedy says.

Juniper had fixed the problem about a year ago, he says, but apparently discovered recently that the flaw was exploitable while working on an interoperability issue.

The advisory, which was among seven posted and available only to Juniper customers and partners, included a patch and workarounds, according to Barry Greene, director of Juniper's security incident response team. "These are all scheduled security advisories as part of a monthly schedule (similar to Microsoft's Patch Tuesday). All have fixed code available and feasible workarounds which can be used and deployed immediately by our customers," Greene said in a statement.

Meanwhile, Praetorian today tested all 256 instances of the TCP option field in the header, Kennedy says, and found the one that causes the router to crash. "The exploit is thus confirmed," he says.

Have a comment on this story? Please click "Discuss" below. If you'd like to contact Dark Reading's editors directly, send us a message. Kelly Jackson Higgins is the Executive Editor of Dark Reading. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
Attackers Leave Stolen Credentials Searchable on Google
Kelly Sheridan, Staff Editor, Dark Reading,  1/21/2021
How to Better Secure Your Microsoft 365 Environment
Kelly Sheridan, Staff Editor, Dark Reading,  1/25/2021
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win an Amazon Gift Card! Click Here
Latest Comment: We need more votes, check the obituaries.
Current Issue
2020: The Year in Security
Download this Tech Digest for a look at the biggest security stories that - so far - have shaped a very strange and stressful year.
Flash Poll
Assessing Cybersecurity Risk in Today's Enterprises
Assessing Cybersecurity Risk in Today's Enterprises
COVID-19 has created a new IT paradigm in the enterprise -- and a new level of cybersecurity risk. This report offers a look at how enterprises are assessing and managing cyber-risk under the new normal.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2021-3317
PUBLISHED: 2021-01-26
KLog Server through 2.4.1 allows authenticated command injection. async.php calls shell_exec() on the original value of the source parameter.
CVE-2013-2512
PUBLISHED: 2021-01-26
The ftpd gem 0.2.1 for Ruby allows remote attackers to execute arbitrary OS commands via shell metacharacters in a LIST or NLST command argument within FTP protocol traffic.
CVE-2021-3165
PUBLISHED: 2021-01-26
SmartAgent 3.1.0 allows a ViewOnly attacker to create a SuperUser account via the /#/CampaignManager/users URI.
CVE-2021-1070
PUBLISHED: 2021-01-26
NVIDIA Jetson AGX Xavier Series, Jetson Xavier NX, TX1, TX2, Nano and Nano 2GB, L4T versions prior to 32.5, contains a vulnerability in the apply_binaries.sh script used to install NVIDIA components into the root file system image, in which improper access control is applied, which may lead to an un...
CVE-2021-1071
PUBLISHED: 2021-01-26
NVIDIA Tegra kernel in Jetson AGX Xavier Series, Jetson Xavier NX, TX1, TX2, Nano and Nano 2GB, all L4T versions prior to r32.5, contains a vulnerability in the INA3221 driver in which improper access control may lead to unauthorized users gaining access to system power usage data, which may lead to...