CVE-2021-34722

Root command execution via unsanitized CLI arguments

Published Sep 9, 2021 · Updated Nov 7, 2024

Command injection in the CLI of Cisco IOS XR Software 7.1.1 through 7.3.1 allows local users to execute commands as root. The CLI improperly sanitizes crafted command arguments before executing them in the underlying Linux environment. Exploitation requires an authenticated account with high privileges and grants a root shell with unrestricted command execution on the device.

CVSS severity6.7
Medium
EPSS probability0.28%
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 the CLI of Cisco IOS XR Software 7.1.1 through 7.3.1 allows local users to execute commands as root. The CLI improperly sanitizes crafted command arguments before executing them in the underlying Linux environment. Exploitation requires an authenticated account with high privileges and grants a root shell with unrestricted command execution on the device.

The record

CVE
CVE-2021-34722
Published
Sep 9, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco IOS XR Software
Classifications
CWE-78, T1059.004
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Sep 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 7, 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 vectorlocal
Required privilegesadmin

What is affected?

ClamAV · Cisco IOS XR Softwareversion=n/a

Published CVSS scores

6.7Cisco Systems, Inc.CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059.004Unix Shell

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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