CVE-2021-33420Public exploitNetwork attack vector

Remote code execution via unrestricted TypedArray constructors

Published Dec 15, 2022 · Updated Apr 21, 2025

Deserialization in inikulin replicator before 1.0.4 allows remote attackers to execute arbitrary code through crafted TypedArray data. The TypedArray fromSerializable function reads an attacker-controlled ctorName, resolves it on the global object, and invokes it with attacker-controlled arr data. Any application that passes untrusted serialized input to decode exposes the privileges and data of its hosting Node.js process.

CVSS severity9.8
Critical
EPSS probability1.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization in inikulin replicator before 1.0.4 allows remote attackers to execute arbitrary code through crafted TypedArray data. The TypedArray fromSerializable function reads an attacker-controlled ctorName, resolves it on the global object, and invokes it with attacker-controlled arr data. Any application that passes untrusted serialized input to decode exposes the privileges and data of its hosting Node.js process.

The record

CVE
CVE-2021-33420
Published
Dec 15, 2022
Updated
Apr 21, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-502
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 15, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 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?

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

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8CISA-ADPCVSS: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 exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data

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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