Vulnerability in Flarum Framework
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.
EPSS: 0.002 (13.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Flarum Framework — versions 0
Weakness classification (CWE)
References
- disclosure@vulncheck.com (release-notes)
- disclosure@vulncheck.com (issue-tracking)
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-39924?
- CVE-2026-39924 is a medium-severity vulnerability in Flarum Framework, classified under Insufficient Session Expiration. CVSS score: 6.8/10. Published 2026-08-05.
- How severe is CVE-2026-39924?
- Medium severity. CVSS v3 base score is 6.8 out of 10.