CVE-2026-85602CWE-807

CVE-2026-85602

Medium · published September 4, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
17.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS v4.0
9.3 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.00261 · 17.7th percentile
Weakness
CWE-807 · Reliance on Untrusted Inputs in a Security Decision
Published
2026-09-04T16:17Z
References (3)
https://github.com/getgrav/grav/security/advisories/GHSA-89j6-8h38-2cc3 · [email protected]https://www.vulncheck.com/advisories/grav-form-plugin-before-9.1.20-recaptcha-v3-authentication-bypass · [email protected]https://github.com/getgrav/grav/security/advisories/GHSA-89j6-8h38-2cc3 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 06 SEP 03:33Z
    EPSS moved — → 0%
    epss
  • 04 SEP 11:30Z
    Grav Form Plugin before 9.1.20 reCAPTCHA v3 Authentication Bypass
    cvelistv5