hCaptcha for WP <= 5.3.0 — Unauthenticated Captcha Verification Bypass
CVE-2026-103347Published · Updated Action summary
Affected: ≤5.3.0Update to 5.4.0 or newer
All remediation steps- Severity
- High7.3
- CVSS
- 7.3CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:LWhat does this vector mean?
AV:NAttack vector- Network
AC:LAttack complexity- Low
PR:NPrivileges required- None
UI:NUser interaction- None
S:UScope- Unchanged
C:LConfidentiality- Low
I:LIntegrity- Low
A:LAvailability- Low
- Weakness
- CWE-804 Guessable CAPTCHA
- Required access
- No account needed
- Exploit prediction (EPSS)
- No score
- CISA KEV
- Not listed
On this page8
Am I affected?
hCaptcha for WP hcaptcha-for-forms-and-more
- Affected≤ 5.3.0
- Patched in5.4.0
Update to 5.4.0 or newer.
You are affected if you run ≤ 5.3.0. Version 5.4.0 and later are not affected by this issue.
- Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under hCaptcha for WP.
- No admin access? Run a passive check of your site. It reads public files only.
- No account is needed to exploit this. Treat any exposed site on an affected version as at risk.
What to do
- Update to version 5.4.0, or a newer patched version
- Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
- Watch hCaptcha for WP to get an email when the next vulnerability is published.
Advisory
Source description from Wordfence Intelligence, credited to bamper1.
The hCaptcha for WP plugin for WordPress is vulnerable to Bypass Vulnerability in all versions up to, and including, 5.3.0. This is due to form action registrations stored exclusively in a WordPress transient that could expire or be evicted, causing get_registered_form() to return null and skip the hCaptcha requirement for auto-verified forms. This makes it possible for unauthenticated attackers to bypass hCaptcha verification on auto-verified forms by waiting for or triggering transient expiration, causing the plugin to skip the captcha check entirely. The site must use AutoVerify (auto-detected hCaptcha integration) for at least one form.
Exploits & references
Proof-of-concept & detection
No public proof-of-concept or detection template is known for this vulnerability.
Advisories & patches
- Advisorywordfence.com
Related CVEs
More in hCaptcha for WP
All 3| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| Medium5.3 | Missing Authorization ≤4.22.0Update to 4.23.0 | CVE-2026-25315 | |
| Medium6.4 | Authenticated (Contributor+) Stored Cross-Site Scripting via cf7-hcaptcha Shortcode ≤4.0.0Update to 4.0.1 | CVE-2024-4014 |
- Medium5.3Missing Authorization
≤4.22.0Update to 4.23.0
- Medium6.4Authenticated (Contributor+) Stored Cross-Site Scripting via cf7-hcaptcha Shortcode
≤4.0.0Update to 4.0.1
Timeline
CVE published
Severity high, CVSS 7.3
Record last updated
Sources & licenses
Wordfence record- Vulnerability data
- Wordfence Intelligence. [object Object] Licensed under the CC BY-SA 4.0.
- CVE® identifiers
- [object Object]. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
- CVSS / CWE
- National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
- VulnCrest content
- Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.