CVE-2020-3602: Cisco StarOS Privilege Escalation Vulnerability

Severity: medium (CVSS 6.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-08 · updated 2026-06-17
Weakness: CWE-20

Description

A vulnerability in the CLI of Cisco StarOS operating system for Cisco ASR 5000 Series Routers could allow an authenticated, local attacker to elevate privileges on an affected device. The vulnerability is due to insufficient input validation of CLI commands. An attacker could exploit this vulnerability by sending crafted commands to the CLI. A successful exploit could allow the attacker to execute arbitrary code with the privileges of the root user on the affected device. To exploit this vulnerability, an attacker would need to have valid credentials on an affected device and know the password for the cli test-commands command.

Affected products

Cisco StarOS: before 21.19.n4 — fixed in 21.19.n4

How to fix

Upgrade to a fixed version: Cisco StarOS 21.19.n4. Check the vendor advisory for mitigations.

References

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