CVE-2020-36604Network attack vector

Prototype pollution via unsafe clone handling

Published Sep 23, 2022 · Updated May 27, 2025

Prototype pollution in hoek before 8.5.1 and 9.x before 9.0.3 allows remote attackers to alter object prototypes via crafted clone input. The clone function converts an object containing the proto key into a prototype instead of treating the key as ordinary data. Exploitation requires an application to pass attacker-controlled objects to clone(); resulting prototype changes can alter downstream confidentiality, integrity, and availability.

CVSS severity8.1
High
EPSS probability1.03%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Prototype pollution in hoek before 8.5.1 and 9.x before 9.0.3 allows remote attackers to alter object prototypes via crafted clone input. The clone function converts an object containing the proto key into a prototype instead of treating the key as ordinary data. Exploitation requires an application to pass attacker-controlled objects to clone(); resulting prototype changes can alter downstream confidentiality, integrity, and availability.

The record

CVE
CVE-2020-36604
Published
Sep 23, 2022
Updated
May 27, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-1321
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 23, 2022CVE publishedPublication date reported by the CVE source.
  2. May 27, 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

8.1NVDCVSS:3.1/AV:N/AC:H/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.

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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-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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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