by Kastro
Paper/Archive/CVE-2026-39923

CVE-2026-39923

Flarum Flarum Framework — Flarum < 1.8.16 Password Reset Token Expiry Bypass via POST /reset

EPSS 0.4%CVSS 9.2
critical.is priorityof 100
35
CVSS 9.2 (CNA)9.2 / 10 × 3027.6Not in CISA KEV+300.0EPSS percentile 37.1.371 × 207.4No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Flarum before 1.8.16 contains a password reset token expiry bypass vulnerability that allows unauthenticated attackers to reuse expired password reset tokens by submitting them directly to the reset processing endpoint. The SavePasswordController::handle() method calls PasswordToken::findOrFail() without performing any expiry validation, allowing attackers to bypass the 24-hour token lifetime enforced only during form rendering and change any account's password to gain an authenticated session.

Affected

ProductAffectedFixed inSource
Flarum Framework< 1.8.161.8.16CNA

Scores by source

VulnCheck (CNA)9.2CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
VulnCheck (CNA)8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

refgithub.com/flarum/framework/releases/tag/v1.8.16refgithub.com/flarum/framework/pull/4545patchgithub.com/flarum/framework/commit/2803058d0f9dc38252326070b46d4484fe5a857dwriteupvulncheck.com/advisories/flarum-password-reset-token-expiry-bypass-via-post-reset