Connect with us

Hi, what are you looking for?


Network Security

Cisco Patches Critical, High Severity Flaws in NX-OS

Cisco informed customers on Wednesday that it has released software updates for several of its products to address critical and high severity vulnerabilities.

Cisco informed customers on Wednesday that it has released software updates for several of its products to address critical and high severity vulnerabilities.

The most serious of the issues is a critical vulnerability related to the existence of insecure default credentials in the NX-OS network operating system running on Cisco Nexus 3000 series and Nexus 3500 platform switches. The flaw, identified as CVE-2016-1329, can be exploited by a remote, unauthenticated attacker to log into a vulnerable device with root privileges via an account that has a default and static password.

The problem is that the account in question, which is created during installation, cannot be changed or removed without affecting the system’s functionality.

The security hole affects Cisco Nexus 3000 Series Switches running NX-OS 6.0(2)U6(1), 6.0(2)U6(2), 6.0(2)U6(3), 6.0(2)U6(4), and 6.0(2)U6(5), and Cisco Nexus 3500 Platform Switches running versions 6.0(2)A6(1), 6.0(2)A6(2), 6.0(2)A6(3), 6.0(2)A6(4), 6.0(2)A6(5), and 6.0(2)A7(1). Users who cannot immediately install the updates that fix the issue can apply workarounds described in Cisco’s advisory.

The networking giant has also released a software update to patch a high severity denial-of-service (DoS) vulnerability in the SNMP input packet processor of Nexus 5500 and 5600 Platform switches, and Nexus 6000 series switches running NX-OS.

An unauthenticated attacker can exploit the flaw, tracked as CVE-2015-6260, to remotely cause the SNMP application to restart by sending a specially crafted SNMP packet to the targeted device. A malicious actor can cause the application to restart multiple times, which could lead to a system-level restart and a DoS condition.

The vulnerability affects NX-OS release 7.1(1)N1(1) and it has been patched with the release of version 7.1(2)N1(1). No workarounds are available.

A different high severity DoS flaw has been found in NX-OS’s TCP stack (CVE-2015-0718). A remote, unauthenticated attacker can send a specially crafted TCP packet to a targeted device and cause it to enter a DoS condition.

Advertisement. Scroll to continue reading.

The issue affects Cisco Nexus 1000V, 3000, 4000, 5000, 6000 and 7000 series switches, and Unified Computing System (UCS) running NX-OS.

A different advisory published by Cisco on Wednesday describes a high severity DoS vulnerability (CVE-2016-1288) in the web proxy framework of the Cisco Web Security Appliance (WSA). A remote attacker can cause a temporary DoS condition on vulnerable devices by sending them malformed HTTPS request packets.

Cisco says it’s not aware of any instances where these vulnerabilities have been exploited for malicious purposes.

Related: Cisco Security Products Plagued by Critical Flaws

Written By

Eduard Kovacs (@EduardKovacs) is a managing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.

Click to comment


Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Join the session as we discuss the challenges and best practices for cybersecurity leaders managing cloud identities.


SecurityWeek’s Ransomware Resilience and Recovery Summit helps businesses to plan, prepare, and recover from a ransomware incident.


People on the Move

Digital executive protection services provider BlackCloak has appointed Ryan Black as CISO.

Joe Levy has been appointed Sophos' permanent CEO, and Jim Dildine has been named the company's CFO.

CISA executive assistant director for cybersecurity Eric Goldstein is leaving the agency after more than three years.

More People On The Move

Expert Insights

Related Content

Identity & Access

Zero trust is not a replacement for identity and access management (IAM), but is the extension of IAM principles from people to everyone and...

Cybersecurity Funding

Network security provider Corsa Security last week announced that it has raised $10 million from Roadmap Capital. To date, the company has raised $50...

Application Security

Virtualization technology giant VMware on Tuesday shipped urgent updates to fix a trio of security problems in multiple software products, including a virtual machine...

Network Security

Attack surface management is nothing short of a complete methodology for providing effective cybersecurity. It doesn’t seek to protect everything, but concentrates on areas...

Network Security

A zero-day vulnerability named HTTP/2 Rapid Reset has been exploited to launch some of the largest DDoS attacks in history.

Application Security

Fortinet on Monday issued an emergency patch to cover a severe vulnerability in its FortiOS SSL-VPN product, warning that hackers have already exploited the...

Identity & Access

Hackers rarely hack in anymore. They log in using stolen, weak, default, or otherwise compromised credentials. That’s why it’s so critical to break the...


Websites of German airports, administration bodies and banks were hit by DDoS attacks attributed to Russian hacker group Killnet