CVE-2023-41100Network attack vector

CAPTCHA bypass via omitted required form field

Published Aug 23, 2023 · Updated Oct 3, 2024

Broken access control in hCaptcha for EXT:form before 2.1.2 allows remote attackers to bypass CAPTCHA validation in TYPO3 forms. The extension's form validator accepts submitted form data when the required CAPTCHA field is absent instead of rejecting the empty value. No authentication or user interaction is required, and the bypass defeats only the CAPTCHA gate on forms configured to use this third-party extension.

CVSS severity5.3
Medium
EPSS probability0.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Broken access control in hCaptcha for EXT:form before 2.1.2 allows remote attackers to bypass CAPTCHA validation in TYPO3 forms. The extension's form validator accepts submitted form data when the required CAPTCHA field is absent instead of rejecting the empty value. No authentication or user interaction is required, and the bypass defeats only the CAPTCHA gate on forms configured to use this third-party extension.

The record

CVE
CVE-2023-41100
Published
Aug 23, 2023
Updated
Oct 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-639, CWE-284, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 23, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 3, 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

5.3MITRECVSS:3.1/AC:L/AV:N/A:L/C:N/I:N/PR:N/S:U/UI:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
CWE-284Improper Access Control
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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