CVE-2026-103514

2FA <= 4.0.0 - Unauthenticated Two-Factor Authentication Bypass

2026-10-01 00:00
Suhayb Ahmed

Strategic Overview

Status
Patched in 4.1.0
Affected Plugin
WP 2FA – Two-factor authentication for WordPress
Affected Version
<= 4.0.0
CVSS
4.3Medium
Weakness type
CWE-287 · Improper Authentication
CVE
CVE-2026-103514
View all WP 2FA – Two-factor authentication for WordPress vulnerabilities

At a glance

CVE-2026-103514 is a medium-severity Improper Authentication vulnerability in the WP 2FA WordPress plugin, affecting versions <= 4.0.0. It carries a CVSS score of 4.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 4.1.0; sites on affected versions should update now. Disclosed October 2026, reported by Suhayb Ahmed.

Vulnerability Overview

The 2FA plugin for WordPress is vulnerable to Two-Factor Authentication Bypass in all versions up to, and including, 4.0.0. This is due to missing per-user invalidation of already-used TOTP codes in the is_valid_authcode() call, which did not receive the user object needed to record and reject previously consumed codes. This makes it possible for Unknown attackers[inject user-level requirements if available and authentication is required] to replay a previously observed TOTP code within its validity window to bypass two-factor authentication and gain unauthorized access to any account, including administrator accounts.

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 interaction from a victim user.

CWE-287: Improper Authentication

WP 2FA <= 4.0.0 carries this weakness at is_valid_authcode(), 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 WP 2FA the fix is 4.1.0: builds <= 4.0.0 are affected, anything from 4.1.0 onward is not.

Remediation

Update to version 4.1.0, 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: WP 2FA 4.1.0 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-103514https://www.wordfence.com/threat-intel/vulnerabilities/id/68757251-28d3-4468-9d46-16c0928d0618https://nvd.nist.gov/vuln/detail/CVE-2026-103514

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C