Cisco Network Services Orchestrator CLI Secure Shell Server Privilege Escalation Vulnerability

A vulnerability in Cisco Network Services Orchestrator (NSO) could allow an authenticated, local attacker to execute arbitrary commands at the level of the account under which Cisco NSO is running, which is root by default. To exploit this vulnerability, an attacker must have a valid account on an affected device.

The vulnerability exists because the affected software incorrectly runs the SFTP user service at the privilege level of the account that was running when the NSO built-in Secure Shell (SSH) server for CLI was enabled. If the NSO built-in SSH server was not enabled, the device is not affected by this vulnerability. An attacker with low-level privileges could exploit this vulnerability by authenticating to an affected device and issuing a series of commands at the SFTP interface. A successful exploit could allow the attacker to elevate privileges to the level of the account under which Cisco NSO is running, which is root by default.

Note: Any user who can authenticate to the built-in SSH server may exploit this vulnerability. By default, all Cisco NSO users have this access if the server is enabled.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nso-priv-esc-XXqRtTfT

Security Impact Rating: High

CVE: CVE-2021-1572

Source:: Cisco Security Advisories