CVE-2026-90977Network attack vectorHinoki check available

Unauthenticated account creation via empty CAPTCHA session

Published Sep 18, 2026 · Updated Sep 18, 2026

CAPTCHA bypass in Clean Login before 1.19 allows remote attackers to create WordPress accounts through the public registration form. The registration handler treats an empty stored CAPTCHA session value as a condition that skips comparison with the submitted answer. The flaw is reachable without authentication when the plugin's CAPTCHA-protected registration form is exposed, removing its anti-automation barrier but not granting a higher WordPress role by itself.

CVSS severity5.3
Medium
EPSS probability0.37%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

CAPTCHA bypass in Clean Login before 1.19 allows remote attackers to create WordPress accounts through the public registration form. The registration handler treats an empty stored CAPTCHA session value as a condition that skips comparison with the submitted answer. The flaw is reachable without authentication when the plugin's CAPTCHA-protected registration form is exposed, removing its anti-automation barrier but not granting a higher WordPress role by itself.

The record

CVE
CVE-2026-90977
Published
Sep 18, 2026
Updated
Sep 18, 2026
Vendor
Alberto Hornero
Product
Clean Login
Classifications
CWE-697, T1136
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 18, 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=0 <1.19

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Alberto Hornero · Clean Loginversion=0 <1.19

Published CVSS scores

5.3WPScan CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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.

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-697Incorrect Comparison
T1136Create Account

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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