Receive Notifications After Form Submitting – Form Notify for Any Forms <= 1.1.10 - Unauthenticated Authentication Bypass via LINE OAuth Callback
Strategic Overview
- Status
- Patched in 1.1.11
- Affected Version
<= 1.1.10- CVSS
- 9.8Critical
- Weakness type
- CWE-287 · Improper Authentication
- CVE
CVE-2026-5229
At a glance
CVE-2026-5229 is a critical-severity Improper Authentication vulnerability in the Receive Notifications After Form Submitting WordPress plugin, affecting versions <= 1.1.10. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 1.1.11; sites on affected versions should update now. Disclosed May 2026, reported by Nabil Irawan.
Vulnerability Overview
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.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.
CWE-287: Improper Authentication
Receive Notifications After Form Submitting <= 1.1.10 carries this weakness at form_notify_line_email, and reaching it takes no account at all. Improper authentication means the mechanism that proves who a caller is can be satisfied without the secret it was supposed to require.
An attacker authenticates as another user — administrators included — without ever knowing a password, so password policies and login rate limits never come into play. For Receive Notifications After Form Submitting the fix is 1.1.11: builds <= 1.1.10 are affected, anything from 1.1.11 onward is not.
Remediation
Update to version 1.1.11, or a newer patched version
How does WordSec protect against this?
This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: Receive Notifications After Form Submitting 1.1.11 closes this, and updating the plugin is the step that ends it.
- Login Security
- Alerts
External References
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C