CVE-2026-116238: pgAdmin 4: The failed login limit can be bypassed, and Flask-Security's own views skip pgAdmin's login and password checks

Vulnerability summary

CVE-2026-116238 is a critical (CVSS 9.2) vulnerability in pgadmin.org pgadmin 4. EPSS estimates a 0.40% chance of exploitation in the next 30 days, higher than 34.6% of scored vulnerabilities.

Timeline

1. 30-10-2026
   PublishedVulnerability first disclosed.

Description

In server mode pgAdmin 4 locks an internal account after MAX_LOGIN_ATTEMPTS failed logins (3 by default). The limit could be bypassed, giving an unauthenticated attacker an unlimited number of password guesses against any internal account, including the administrator's, in the default configuration: - Flask-Security registers its own views next to pgAdmin's. A login submitted to its /login view was checked and logged in without pgAdmin's failed login count or lock. Its /verify view checked a signed-in user's password without limit, its /change view changed a password without pgAdmin's change password permission or re-encrypting the user's saved server passwords, and its /reset views sent and applied password resets for accounts that are not internal or are locked. - The internal account was looked up by its exact username, while the login form matches the email ignoring case, so a login with the username typed in another case was neither counted nor checked for the lock. - With LDAP or webserver authentication also configured, a wrong internal password was never counted, and with Kerberos or webserver authentication configured a guess could be answered without being counted. In addition, where accounts from different authentication sources share an email address, a password reset could be sent for, or applied to, an account from another source, and the About box showed the server configuration to a user whose email was that of an administrator's account. The fix refuses submissions to Flask-Security's own views, counts every failed internal login however the username is typed and whatever other sources are configured, no longer lets a login that posts a password fall back to an authentication source that does not check it, and locks only internal authentication. Password resets and the About box act only on the user's own internal account. Desktop mode is not affected. This issue affects pgAdmin 4: before 9.19.

• CWE-307Improper Restriction of Excessive Authentication AttemptsThe product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.
• CWE-863Incorrect AuthorizationThe product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.