CVE-2021-44827Public exploitNetwork attack vector

Root command execution via IPv6 address injection

Published Mar 4, 2022 · Updated Aug 4, 2024

OS command injection in TP-Link Archer C20i firmware 0.9.1 3.2 v003a.0 Build 170221 Rel.55462n allows remote authenticated users to execute commands. The network-interface configuration handler passes the X_TP_ExternalIPv6Address HTTP value to an OS command without neutralizing shell syntax. Access to the authenticated management interface permits arbitrary command execution with root privileges.

CVSS severity8.8
High
EPSS probability53.96%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in TP-Link Archer C20i firmware 0.9.1 3.2 v003a.0 Build 170221 Rel.55462n allows remote authenticated users to execute commands. The network-interface configuration handler passes the X_TP_ExternalIPv6Address HTTP value to an OS command without neutralizing shell syntax. Access to the authenticated management interface permits arbitrary command execution with root privileges.

The record

CVE
CVE-2021-44827
Published
Mar 4, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-78, T1059.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 4, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.0NIST NVDAV:N/AC:L/Au:S/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)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

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

Public exploit references

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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