CVE-2026-88828Network attack vectorHinoki check available

Blocked-account access via incomplete authentication checks

Published Sep 28, 2026 · Updated Sep 28, 2026

Authentication restriction bypass in YoOhw Studio Blacklist Manager 1.3.0 through 2.3.1 lets remote authenticated users retain blocked-account access. The plugin does not apply its blocked-user decision to every WordPress authentication path, allowing valid blocked accounts to authenticate without enforcement or logging. Exploitation requires control of a blocked account and valid credentials; access remains limited to that account's existing privileges.

CVSS severityUnavailable
Unscored
EPSS probability0.17%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Authentication restriction bypass in YoOhw Studio Blacklist Manager 1.3.0 through 2.3.1 lets remote authenticated users retain blocked-account access. The plugin does not apply its blocked-user decision to every WordPress authentication path, allowing valid blocked accounts to authenticate without enforcement or logging. Exploitation requires control of a blocked account and valid credentials; access remains limited to that account's existing privileges.

The record

CVE
CVE-2026-88828
Published
Sep 28, 2026
Updated
Sep 28, 2026
Vendor
YoOhw Studio
Product
Blacklist Manager
Classifications
T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 28, 2026Record 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=1.3.0 <2.3.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

YoOhw Studio · Blacklist Managerversion=1.3.0 <2.3.2

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1078Valid Accounts

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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