{"id":"CVE-2026-85602","title":"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","summary":"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, a…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","cwe":["CWE-807"],"published":"2026-09-04","updated":"2026-09-08","sourceUpdated":"2026-09-08T20:05:53.177","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-85602","references":[{"url":"https://github.com/getgrav/grav/security/advisories/GHSA-89j6-8h38-2cc3","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/grav-form-plugin-before-9.1.20-recaptcha-v3-authentication-bypass","label":"disclosure@vulncheck.com"},{"url":"https://github.com/getgrav/grav/security/advisories/GHSA-89j6-8h38-2cc3","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.00261,"epssPercentile":0.18097,"ingestedAt":"2026-09-06T01:47:58.358Z","slug":"CVE-2026-85602","body":"## Overview\n\nThe 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}