Is there a public exploit for CVE-2026-123746?

No public exploit for CVE-2026-123746 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-123746?

CVE-2026-123746 scores CVSS 2.3 (v4.0), rated low.

What does CVE-2026-123746 affect?

CVE-2026-123746 affects sensiolabs symfony.

2.3 Low

The Symfony Security HTTP component AuthenticatorManager::authenticateUser() does not run the firewall user checker’s checkPostAuth()…

CVE-2026-123746

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…

Assessment

CVSS: 2.3 (v4.0)
Severity: Low
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 6 November 2026
Last updated: 6 November 2026
Affected: sensiolabs · symfony
Assigner: Checkmarx

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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