CVE-2025-48940

high

Description

MyBB is free and open source forum software. Prior to version 1.8.39, the upgrade component does not validate user input properly, which allows attackers to perform local file inclusion (LFI) via a specially crafted parameter value. In order to exploit the vulnerability, the installer must be unlocked (no `install/lock` file present) and the upgrade script must be accessible (by re-installing the forum via access to `install/index.php`; when the forum has not yet been installed; or the attacker is authenticated as a forum administrator). MyBB 1.8.39 resolves this issue.

References

https://mybb.com/versions/1.8.39

https://github.com/mybb/mybb/security/advisories/GHSA-q4jv-xwjx-37cp

https://github.com/mybb/mybb/commit/6e6cfbd524d9101b51e1278ecf520479b64b0f00

Details

Source: Mitre, NVD

Published: 2025-06-02

Updated: 2025-06-02

Risk Information

CVSS v2

Base Score: 8.3

Vector: CVSS2#AV:N/AC:L/Au:M/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 7.2

Vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.00051