Overview
Multiple vulnerabilities in the authentication mechanism of Cisco Data Center Network Manager (dcnm) (cve-2019-15975, cve-2019-15976, cve-2019-15977) may allow unauthorized remote attackers to bypass authentication and perform arbitrary operations with administrative privileges on the affected devices.
- CVE-2019-15975: Cisco dcnm rest API authentication bypass vulnerability
The vulnerability exists because the static encryption key is shared between installations. An attacker can exploit this vulnerability by using a static key to make a valid session token. Successful exploitation could allow an attacker to perform arbitrary operations through a rest API with administrative privileges.
- CVE-2019-15976: Cisco dcnm soap API authentication bypass vulnerability
The vulnerability exists because the static encryption key is shared between installations. An attacker can exploit this vulnerability by using a static key to make a valid session token. Successful exploitation may allow an attacker to perform arbitrary operations through a soap API with administrative privileges.
- CVE-2019-15977: Cisco dcnm authentication bypass vulnerability
Cisco dcnm has a vulnerability in its web based management interface due to the presence of static credentials. An attacker can exploit this vulnerability by authenticating the user interface with static credentials. A successful exploit could allow an attacker to access specific parts of the web interface and obtain certain confidential information from the affected device. This information can be used to further attack the system.
The official score of the three vulnerabilities is 9.8.
Base 9.8 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X
The vulnerability was fixed on January 3. Steven Seeley, a security researcher who initially discovered the vulnerability this week, disclosed the POC, and Cisco urged customers to update it in a timely manner.
References:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200102-dcnm-auth-bypass
https://threatpost.com/cisco-dcnm-flaw-exploit/151949/
Affected Versions
- Microsoft Windows, Linux, Virtual device platform
Cisco DCNM < 11.3 (1)
Unaffected Versions
- Microsoft Windows, Linux, Virtual device platform
Cisco DCNM >= 11.3 (1)
Solution
The above vulnerability has been fixed in Cisco dcnm 11.3 (1) and later. It is recommended that affected users upgrade and update in time to prevent risks.
The download page is as follows:
https://software.cisco.com/download/home
- Click browse all.
- Select cloud and Systems Management > Data Center Infrastructure Management > data center network manager.
- Select the version from the left pane of the data center network manager page.
Statement
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About NSFOCUS
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