Vulnerability Description
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 Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/flarum/framework/commit/5f080293a029d0d273eb9678d597c74ea86a3
- 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-acc
FAQ
What is CVE-2026-39924?
CVE-2026-39924 is a vulnerability with a CVSS score of 6.8 (MEDIUM). 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, b...
How severe is CVE-2026-39924?
CVE-2026-39924 has been rated MEDIUM with a CVSS base score of 6.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-39924?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.