Vulnerability in Getgrav Grav-Plugin-Form
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (28.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 28.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Affected products
Weakness classification (CWE)
References
- github.com/getgrav/grav/security/advisories/GHSA-89j6-8h38-2cc3 (vendor-advisory)
- www.vulncheck.com/advisories/grav-form-plugin-before-9.1.20-recaptcha-v3-authen… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-85602?
- CVE-2026-85602 is a medium-severity vulnerability in Getgrav Grav-Plugin-Form, classified under CWE-807. CVSS score: 5.3/10. Published 2026-09-04.
- How severe is CVE-2026-85602?
- Medium severity. CVSS v3 base score is 5.3 out of 10.