CVE-2020-5232Network attack vector

Authenticated takeover of transferred domain names

Published Jan 30, 2020 · Updated Aug 4, 2024

Improper authorization in Ethereum Name Service ENS before 0.4.0 allows remote authenticated users to reclaim transferred domain names. The published advisory identifies the ENS registry as the affected locus but does not disclose the specific state mutation or authorization error used to plant the trapdoor. Exploitation requires prior ownership of a name and a later transfer accepted by another user; the former owner can then restore control without that user's consent.

CVSS severity8.7
High
EPSS probability1.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Ethereum Name Service ENS before 0.4.0 allows remote authenticated users to reclaim transferred domain names. The published advisory identifies the ENS registry as the affected locus but does not disclose the specific state mutation or authorization error used to plant the trapdoor. Exploitation requires prior ownership of a name and a later transfer accepted by another user; the former owner can then restore control without that user's consent.

The record

CVE
CVE-2020-5232
Published
Jan 30, 2020
Updated
Aug 4, 2024
Vendor
Ethereum Name Service
Product
ENS
Classifications
CWE-285
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 30, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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=< 0.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Ethereum Name Service · ENSversion=< 0.4.0

Published CVSS scores

8.7GitHub CNACVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-285Improper Authorization

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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