CVE-2021-1443Network attack vector

Authenticated OS command injection via unsanitized configuration

Published Mar 24, 2021 · Updated Nov 8, 2024

Command injection in Cisco IOS XE Software allows remote authenticated users to execute arbitrary code with root privileges through the web UI. The web UI parses values from a specific configuration file without proper sanitization, then an API call causes those values to reach an operating-system command context. Exploitation requires privileged device credentials and an enabled HTTP Server feature; successful execution can compromise the device operating system.

CVSS severity5.5
Medium
EPSS probability2.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Cisco IOS XE Software allows remote authenticated users to execute arbitrary code with root privileges through the web UI. The web UI parses values from a specific configuration file without proper sanitization, then an API call causes those values to reach an operating-system command context. Exploitation requires privileged device credentials and an enabled HTTP Server feature; successful execution can compromise the device operating system.

The record

CVE
CVE-2021-1443
Published
Mar 24, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco IOS XE Software
Classifications
CWE-78, CWE-77, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 24, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ClamAV · Cisco IOS XE Softwareversion=n/a

Published CVSS scores

8.5NVDAV:N/AC:M/Au:S/C:C/I:C/A:C
5.5Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:N
7.2NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in OS Command ('OS Command Injection')
CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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