CVE-2021-4329

Arbitrary code execution via inherited operation lookup

Published Mar 5, 2023 · Updated Mar 5, 2025

Command injection in json-logic-js 2.0.0 allows attackers to execute arbitrary JavaScript through crafted JsonLogic operations. logic.js resolves operation names through inherited properties of its operations object and invokes the resulting function with rule-supplied arguments. Exploitation requires an application to evaluate attacker-controlled rules and runs code with that application process's privileges.

CVSS severity9.3
Critical
EPSS probability2.21%
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 json-logic-js 2.0.0 allows attackers to execute arbitrary JavaScript through crafted JsonLogic operations. logic.js resolves operation names through inherited properties of its operations object and invokes the resulting function with rule-supplied arguments. Exploitation requires an application to evaluate attacker-controlled rules and runs code with that application process's privileges.

The record

CVE
CVE-2021-4329
Published
Mar 5, 2023
Updated
Mar 5, 2025
Vendor
Jeremy Wadhams
Product
json-logic-js
Classifications
CWE-77, T1059.007
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Mar 5, 2023CVE publishedPublication date reported by the CVE source.
  2. Mar 5, 2025Record 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=2.0.0

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Jeremy Wadhams · json-logic-jsversion=2.0.0

Published CVSS scores

9.3GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
5.2VulDBAV:A/AC:L/Au:S/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
5.5VulDBCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

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)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1059.007JavaScript/JScript

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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