CVE-2021-39203Network attack vector

Authenticated private-content access via block-editor authorization bypass

Published Sep 9, 2021 · Updated Aug 4, 2024

Authorization bypass in WordPress 5.8 beta 1 allows remote authenticated users to view private post types and data through the block editor. The published advisory does not identify the affected function or explain how the block editor fails to enforce the underlying content permissions. An account lacking permission to view the targeted private content is required; the disclosed impact is unauthorized reading or privilege expansion within the editor.

CVSS severity6.8
Medium
EPSS probability0.94%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in WordPress 5.8 beta 1 allows remote authenticated users to view private post types and data through the block editor. The published advisory does not identify the affected function or explain how the block editor fails to enforce the underlying content permissions. An account lacking permission to view the targeted private content is required; the disclosed impact is unauthorized reading or privilege expansion within the editor.

The record

CVE
CVE-2021-39203
Published
Sep 9, 2021
Updated
Aug 4, 2024
Vendor
WordPress.org
Product
WordPress
Classifications
CWE-200, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 9, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.8 beta 1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

WordPress.org · WordPressversion=5.8 beta 1

Published CVSS scores

6.8GitHub CNACVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/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.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1190Exploit Public-Facing Application

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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