CVE-2025-48940 — MyBB's upgrade component vulnerable to local file inclusion
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 i…
Published: 2025-06-02 · CVSS: 7.2 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7