CVE-2021-21388Network attack vector

OS command execution via manipulated string prototypes

Published Apr 29, 2021 · Updated Aug 3, 2024

Command injection in systeminformation before 5.6.4 allows attackers to execute OS commands through crafted API parameters. The inetLatency(), inetChecksite(), services(), and processLoad() paths sanitize values while trusting mutable string-prototype behavior, letting a manipulated prototype bypass filtering before command construction. Exploitation requires a consuming application to pass attacker-controlled values into an affected function, and commands run with the Node.js process privileges.

CVSS severity8.9
High
EPSS probability1.85%
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 systeminformation before 5.6.4 allows attackers to execute OS commands through crafted API parameters. The inetLatency(), inetChecksite(), services(), and processLoad() paths sanitize values while trusting mutable string-prototype behavior, letting a manipulated prototype bypass filtering before command construction. Exploitation requires a consuming application to pass attacker-controlled values into an affected function, and commands run with the Node.js process privileges.

The record

CVE
CVE-2021-21388
Published
Apr 29, 2021
Updated
Aug 3, 2024
Vendor
Sebastian Hildebrandt
Product
systeminformation
Classifications
CWE-20, CWE-78, CWE-77, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 29, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 5.6.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Sebastian Hildebrandt · systeminformationversion=< 5.6.4

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.9GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/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 exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
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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