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.

Network Security

10:35 AM
Larry Loeb
Larry Loeb
Larry Loeb

Why Cisco's DCNM Is in a World of Trouble

Vendor's Data Center Network Manager (DCNM) has racked up three critical authentication bypass vulnerabilities at the top of the list of 12 separate problems that were announced on January 2.

Cisco's Data Center Network Manager (DCNM) has been found to be in a world of trouble, racking up three critical authentication bypass vulnerabilities at the top of the list of 12 separate problems that were announced on January 2, 2020. These three have a CVSS of 9.8 out of 10, so they are serious.

Cisco says in a security advisory about the problems that the vulnerabilities "could allow an unauthenticated, remote attacker to bypass authentication and execute arbitrary actions with administrative privileges on an affected device."

While Cisco has released software updates that it says will address and fix the reported problems, there are "no workarounds that address these vulnerabilities."

These vulnerabilities affect Cisco DCNM software releases earlier than Release 11.3(1) for Microsoft Windows, Linux and virtual appliance platforms.

The vulnerabilities are said by Cisco to not be dependent on one another. That means that exploitation of one of the vulnerabilities is not required to exploit another vulnerability. Cisco also says that a software release which is affected by one of the vulnerabilities may not be affected by the other vulnerabilities.

One of the vulnerabilities (CVE-2019-15975) is in the REST API endpoint of Cisco DCNM. Cisco says that the vulnerability exists because "a static encryption key is shared between installations." That means that an attacker could exploit it by using the static key to craft a valid session token. A successful exploit could then allow the attacker to perform arbitrary actions by use of the REST API with administrative privileges.

CVE-2019-15976 is basically the same problem of a static key existing between installations, but in the SOAP API endpoint of Cisco DCNM. The same results of remote attack could occur through the use of a differing API than before.

A vulnerability (CVE-2019-15977) is also present in the web-based management interface of Cisco DCNM that could once again allow an unauthenticated, remote attacker to bypass authentication on an affected device.

This time it's the presence of static credentials causing the problem. An attacker could use the static credentials to authenticate malware that attacks through the user interface. A successful attack could then access a specific section of the web interface and obtain confidential information from an affected device. This information could be used in further attacks against the system.

The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that they described in the advisory.

Security firm Tenable says that by utilizing these authentication bypass vulnerabilities, attackers could in their exploits leverage the remaining flaws patched by Cisco, which include command injection vulnerabilities (CVE-2019-15978, CVE-2019-15979), SQL injection vulnerabilities (CVE-2019-15984, CVE-2019-15985), path traversal vulnerabilities (CVE-2019-15980, CVE-15981, CVE-2019-15982) and an XML external entity vulnerability (CVE-2019-15983).

Eleven of the vulnerabilities were discovered and reported to Cisco by Steven Seeley of Source Incite. Cisco's software update also patched CVE-2019-15999, which is a vulnerability in the DCNM's JBoss Enterprise Application Platform (EAP) reported by Harrison Neal of PatchAdvisor. The authentication settings on the EAP were evidently incorrectly configured.

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.

Comment  | 
Print  | 
More Insights
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 11/19/2020
New Proposed DNS Security Features Released
Kelly Jackson Higgins, Executive Editor at Dark Reading,  11/19/2020
How to Identify Cobalt Strike on Your Network
Zohar Buber, Security Analyst,  11/18/2020
Register for Dark Reading Newsletters
White Papers
Cartoon Contest
Write a Caption, Win an Amazon Gift Card! Click Here
Latest Comment: This comment is waiting for review by our moderators.
Current Issue
2021 Top Enterprise IT Trends
We've identified the key trends that are poised to impact the IT landscape in 2021. Find out why they're important and how they will affect you today!
Flash Poll
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
PUBLISHED: 2020-11-24
499ES EtherNet/IP (ENIP) Adaptor Source Code is vulnerable to a stack-based buffer overflow, which may allow an attacker to send a specially crafted packet that may result in a denial-of-service condition or code execution.
PUBLISHED: 2020-11-24
An ACL bypass flaw was found in pacemaker before 1.1.24-rc1 and 2.0.5-rc2. An attacker having a local account on the cluster and in the haclient group could use IPC communication with various daemons directly to perform certain tasks that they would be prevented by ACLs from doing if they went throu...
PUBLISHED: 2020-11-24
Barco wePresent WiPG-1600W firmware includes a hardcoded API account and password that is discoverable by inspecting the firmware image. A malicious actor could use this password to access authenticated, administrative functions in the API. Affected Version(s):,,,
PUBLISHED: 2020-11-24
HRSALE 2.0.0 allows XSS via the admin/project/projects_calendar set_date parameter.
PUBLISHED: 2020-11-24
A flaw was discovered in WildFly before 21.0.0.Final where, Resource adapter logs plain text JMS password at warning level on connection error, inserting sensitive information in the log file.