CVE-2026-85602

The Grav Form plugin (getgrav/grav-plugin-form) versions 8.0.6 through 9.1.19 select the reCAPTCHA version to validate based solely on which response field key is present in the submitted payload. On a site configured for reCAPTCHA v3, an anonymous attacker can place their v3 token under the v2 field name (g-recaptcha-response instead of token), causing validation to use the v2 branch, which never applies the score threshold or verifies the expected action. This results in a complete bypass of reCAPTCHA v3 bot protection. The issue is fixed in version 9.1.20.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/getgrav/grav/security/advisories/GHSA-89j6-8h38-2cc3
https://www.vulncheck.com/advisories/grav-form-plugin-before-9.1.20-recaptcha-v3-authentication-bypass
https://github.com/getgrav/grav/security/advisories/GHSA-89j6-8h38-2cc3

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-04 12:17

Updated : 2026-09-08 20:05

NVD link : CVE-2026-85602

Mitre link : CVE-2026-85602

CVE.ORG link : CVE-2026-85602

JSON object : View

Products Affected

No product.

CWE

CWE-807

Reliance on Untrusted Inputs in a Security Decision

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