CVE-2021-34719

Authenticated CLI privilege escalation

Published Sep 9, 2021 · Updated Nov 7, 2024

Cisco IOS XR Software CLI privilege escalation allows remote authenticated users with low-privileged accounts to execute arbitrary commands as root on affected devices. The CLI insufficiently validates command-line arguments, so crafted input to a specific command reaches the underlying root shell. Exploitation requires authentication and local device access; successful exploitation can compromise device confidentiality, integrity, and availability.

CVSS severity7.8
High
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

Cisco IOS XR Software CLI privilege escalation allows remote authenticated users with low-privileged accounts to execute arbitrary commands as root on affected devices. The CLI insufficiently validates command-line arguments, so crafted input to a specific command reaches the underlying root shell. Exploitation requires authentication and local device access; successful exploitation can compromise device confidentiality, integrity, and availability.

The record

CVE
CVE-2021-34719
Published
Sep 9, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco IOS XR Software
Classifications
CWE-78, T1068
Attack vector
local
Privileges
authenticated

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 privilegesauthenticated

What is affected?

ClamAV · Cisco IOS XR Softwareversion=n/a

Published CVSS scores

7.8Cisco Systems, Inc.CVSS:3.1/AV:L/AC:L/PR:L/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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1068Exploitation for Privilege Escalation

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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