CVE-2021-1443: Cisco IOS XE Software Web UI OS Command Injection Vulnerability

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-24 · updated 2026-06-17
Weakness: CWE-77

Description

A vulnerability in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker to execute arbitrary code with root privileges on the underlying operating system of an affected device. The vulnerability exists because the affected software improperly sanitizes values that are parsed from a specific configuration file. An attacker could exploit this vulnerability by tampering with a specific configuration file and then sending an API call. A successful exploit could allow the attacker to inject arbitrary code that would be executed on the underlying operating system of the affected device. To exploit this vulnerability, the attacker would need to have a privileged set of credentials to the device.

Affected products

Cisco IOS XE: 16.9.1, 16.9.1a, 16.9.1b, 16.9.1c, 16.9.1d, 16.9.1s (+55)

References

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