Auth bypass in M615926 Receive Notifications After Form Submitting – Notify For Any Forms

CVE-2026-5229

The Form Notify plugin for WordPress is vulnerable to Authentication Bypass in versions up to and including 1.1.10. This is due to the plugin trusting user-controlled cookie data to determine which WordPress account to authenticate after a LINE OAuth login. When LINE doesn't provide an email address (which is common), the plugin falls back to reading the 'form_notify_line_email' cookie value without verifying that the LINE account is associated with that email address. This makes it possible for unauthenticated attackers to gain access to any user account on the site, including administrator accounts, by completing a LINE OAuth flow with their own LINE account while injecting a malicious cookie containing the target victim's email address.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (64.4th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-5229: held from 0.007 to 0.011.

EPSS over last 30 days · oldest: 0.007 · newest: 0.011 · change: +0.004

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-5229?
CVE-2026-5229 is a critical-severity vulnerability in M615926 Receive Notifications After Form Submitting – Notify For Any Forms, classified under Improper Authentication. CVSS score: 9.8/10. Published 2026-05-15.
How severe is CVE-2026-5229?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-5229 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.