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

No history.

Information

Published : 2026-08-05 16:16

Updated : 2026-09-09 20:35

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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