CVE-2021-44223Public exploitNetwork attack vector

Remote code execution via plugin update confusion

Published Nov 25, 2021 · Updated Aug 4, 2024

Plugin update confusion in WordPress before 5.8 allows remote attackers to execute arbitrary code through a supply-chain attack. Core submits installed plugin slugs for WordPress.org update matching without an Update URI exclusion, allowing a directory package with a matching slug to replace a custom plugin. Exposure requires an unclaimed, directory-compliant custom-plugin slug; an accepted malicious replacement runs with site privileges when installed manually or automatically.

CVSS severity9.8
Critical
EPSS probability28.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Plugin update confusion in WordPress before 5.8 allows remote attackers to execute arbitrary code through a supply-chain attack. Core submits installed plugin slugs for WordPress.org update matching without an Update URI exclusion, allowing a directory package with a matching slug to replace a custom plugin. Exposure requires an unclaimed, directory-compliant custom-plugin slug; an accepted malicious replacement runs with site privileges when installed manually or automatically.

The record

CVE
CVE-2021-44223
Published
Nov 25, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1195.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 25, 2021CVE 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?

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

9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.1MITRECVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

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 exploitPublished

Weakness, pattern, technique

T1195.002Compromise Software Supply Chain

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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