CVE-2026-39924

Flarum before 1.8.16 contains an improper session invalidation vulnerability that allows attackers who hold a valid session token to retain full account access after a victim changes their password, because the access_tokens table is never cleared on password change events. The TokensClearer::clearPasswordTokens() function only removes rows from the password_tokens table while leaving all active session cookies and API bearer tokens intact, including long-lived RememberAccessToken entries, and administrator-forced password resets via the user update endpoint are equally ineffective at revoking attacker-held sessions.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/flarum/framework/commit/5f080293a029d0d273eb9678d597c74ea86a3bcc
https://github.com/flarum/framework/pull/4546
https://github.com/flarum/framework/releases/tag/v1.8.16
https://www.vulncheck.com/advisories/flarum-session-persistence-via-improper-access-token-revocation

Configurations

No configuration.

History

23 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Flarum antes de 1.8.16 contiene una vulnerabilidad de invalidación de sesión impropia que permite a los atacantes que poseen un token de sesión válido retener acceso completo a la cuenta después de que una víctima cambia su contraseña, porque la tabla access_tokens nunca se borra en los eventos de cambio de contraseña. La función TokensClearer::clearPasswordTokens() solo elimina filas de la tabla password_tokens mientras deja intactas todas las cookies de sesión activas y los tokens portadores de API, incluidas las entradas RememberAccessToken de larga duración, y los restablecimientos de contraseña forzados por el administrador a través del endpoint de actualización de usuario son igualmente ineficaces para revocar las sesiones en poder del atacante.

Information

Published : 2026-08-05 16:16

Updated : 2026-10-23 21:10

NVD link : CVE-2026-39924

Mitre link : CVE-2026-39924

CVE.ORG link : CVE-2026-39924

JSON object : View

Products Affected

No product.

CWE

CWE-613

Insufficient Session Expiration

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The TokensClearer::clearPasswordTokens() function only removes rows from the password_tokens table while leaving all active session cookies and API bearer tokens intact, including long-lived RememberAccessToken entries, and administrator-forced password resets via the user update endpoint are equally ineffective at revoking attacker-held sessions."}, {"lang": "es", "value": "Flarum antes de 1.8.16 contiene una vulnerabilidad de invalidaci\u00f3n de sesi\u00f3n impropia que permite a los atacantes que poseen un token de sesi\u00f3n v\u00e1lido retener acceso completo a la cuenta despu\u00e9s de que una v\u00edctima cambia su contrase\u00f1a, porque la tabla access_tokens nunca se borra en los eventos de cambio de contrase\u00f1a. La funci\u00f3n TokensClearer::clearPasswordTokens() solo elimina filas de la tabla password_tokens mientras deja intactas todas las cookies de sesi\u00f3n activas y los tokens portadores de API, incluidas las entradas RememberAccessToken de larga duraci\u00f3n, y los restablecimientos de contrase\u00f1a forzados por el administrador a trav\u00e9s del endpoint de actualizaci\u00f3n de usuario son igualmente ineficaces para revocar las sesiones en poder del atacante."}], "lastModified": "2026-10-23T21:10:00.157", "sourceIdentifier": "disclosure@vulncheck.com"}