CVE-2026-39924

Flarum < 1.8.16 Session Persistence via Improper Access Token Revocation

Published Aug 5, 2026 CVSS 4.0 · 7.6 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Flarum flarum
CPEs cpe:2.3:a:flarum:flarum:*:*:*:*:*:*:*:*
Vendors & Products Flarum flarum
Type Values Removed Values Added
First Time appeared Flarum
Flarum framework
Vendors & Products Flarum
Flarum framework
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Flarum < 1.8.16 Session Persistence via Improper Access Token Revocation
Weaknesses CWE-613
References
Metrics cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 7.6, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Nov 8, 2026, 2:02 PM
Reserved
Apr 7, 2026, 8:57 PM
Status
Deferred
Published
Aug 5, 2026, 4:16 PM
Modified
Oct 23, 2026, 9:10 PM