CVE-2026-39923

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 v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-05 16:16

Updated : 2026-09-09 20:35

NVD link : CVE-2026-39923

Mitre link : CVE-2026-39923

CVE.ORG link : CVE-2026-39923

JSON object : View

Products Affected

No product.

CWE

CWE-324

Use of a Key Past its Expiration Date

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