Vulnerabilities

Vulnerability · CVE-2026-123746

Symfony: Programmatic Logins Skip the checkPostAuth() Method of User Checkers

Published Nov 6, 2026 · catalog updated Nov 7, 2026 · Symfony: Programmatic Logins Skip

Last checked Nov 8, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2026-123746. EPSS is 0.28%. Act only if a listed version of Symfony: Programmatic Logins Skip is installed.

Severity

Low2.3

Known exploitation

Not in CISA/VulnCheck KEV

EPSS

0.28%

Remediation

Advisory link

Affected products

Debian:12 symfony · Debian:13 symfony · Debian:14 symfony · vendor sensiolabs symfony

The Symfony Security HTTP component AuthenticatorManager::authenticateUser() does not run the firewall user checker’s checkPostAuth() method when a user is authenticated programmatically, allowing an account rejected by a custom user checker, such as an expired account, to be authenticated in Symfony versions prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, and 8.x prior to 8.1.11. AuthenticatorManager::authenticateUser() is used by UserAuthenticatorInterface::authenticateUser() and by the SecurityBundle’s Security::login() to authenticate a user programmatically, but it does not dispatch the security.authentication.success event, on which checkPostAuth() runs. The fix for CVE-2024-50341 made Security::login() call checkPreAuth(), but checkPostAuth() was still skipped. As a result, an account rejected by a custom user checker in checkPostAuth() is refused by form login and the other authenticators of the firewall, but can still be authenticated programmatically. Applications are affected when they use a custom user checker that rejects users in checkPostAuth() and authenticate users programmatically, for example after a password reset or an e-mail verification link. A user whose account is rejected can then obtain an authenticated session through that flow. The default user checker does nothing in checkPostAuth(), so the default configuration is not affected. The fix makes AuthenticatorManager::authenticateUser() dispatch the security.authentication.success event once the token is created and before it is stored, as authentications through the firewall do, so that checkPostAuth() runs and can reject the user.