---
cve: "CVE-2026-39923"
severity: "CRITICAL"
cvss: 9.2
epss: "26%"
vendor: "flarum"
kev: false
exploited: false
published: "2026-08-05 16:16:55"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-15T19:22:44+02:00"
---

# CVE-2026-39923

> 9.2 CRITICAL · 🧪 PoC

## Beschreibung

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.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- a2260e4a62f21591e1a9ae9b11c7db07c6507766 (Commit)
- 2803058d0f9dc38252326070b46d4484fe5a857d (Commit)

## Referenzen

- <https://github.com/flarum/framework/releases/tag/v1.8.16>
- <https://github.com/flarum/framework/pull/4545>
- <https://github.com/flarum/framework/commit/2803058d0f9dc38252326070b46d4484fe5a857d>
- <https://www.vulncheck.com/advisories/flarum-password-reset-token-expiry-bypass-via-post-reset>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-39923) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_