CVE-2021-44882Network attack vector

Unauthenticated command execution via crafted HNAP1 request

Published Feb 4, 2022 · Updated Aug 4, 2024

Command injection in D-Link DIR-878 firmware 1.30B08 and earlier allows remote attackers on the LAN to execute arbitrary commands. The twsystem function passes attacker-controlled values from a crafted HNAP1 POST request into command execution without neutralizing command syntax. The HNAP1 endpoint must be reachable from the local network; successful exploitation requires no authentication or user interaction.

CVSS severity9.8
Critical
EPSS probability4.51%
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 D-Link DIR-878 firmware 1.30B08 and earlier allows remote attackers on the LAN to execute arbitrary commands. The twsystem function passes attacker-controlled values from a crafted HNAP1 POST request into command execution without neutralizing command syntax. The HNAP1 endpoint must be reachable from the local network; successful exploitation requires no authentication or user interaction.

The record

CVE
CVE-2021-44882
Published
Feb 4, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-77, T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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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