CVE-2021-28151Known exploitationPublic exploitNetwork attack vector

Guest-authenticated root command execution via unfiltered ping destination

Published May 6, 2021 · Updated Aug 3, 2024

OS command injection in Hongdian H8922 3.0.5 allows remote authenticated users to execute arbitrary commands as root via tools.cgi. The tools.cgi ping handler passes the Destination field to a shell command without filtering metacharacters, so a semicolon terminates the intended ping and starts another command. The interface accepts the low-privilege guest account and its published default credentials, giving successful attackers full control of the device.

CVSS severity8.8
High
EPSS probability27.91%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in Hongdian H8922 3.0.5 allows remote authenticated users to execute arbitrary commands as root via tools.cgi. The tools.cgi ping handler passes the Destination field to a shell command without filtering metacharacters, so a semicolon terminates the intended ping and starts another command. The interface accepts the low-privilege guest account and its published default credentials, giving successful attackers full control of the device.

The record

CVE
CVE-2021-28151
Published
May 6, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-78, T1059.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 6, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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

9.0NVDAV:N/AC:L/Au:S/C:C/I:C/A:C
8.8NVDCVSS:3.1/AV:N/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.

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 exploitationReported
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.

Reported exploitation

Technologies

Your stack

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Your stack

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