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 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.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-48940?
CVE-2025-48940 is classified as a high severity vulnerability due to its potential for local file inclusion.
How do I fix CVE-2025-48940?
To mitigate CVE-2025-48940, upgrade MyBB to version 1.8.39 or later.
What type of vulnerability is CVE-2025-48940?
CVE-2025-48940 is a local file inclusion (LFI) vulnerability.
What versions of MyBB are affected by CVE-2025-48940?
Versions of MyBB prior to 1.8.39 are affected by CVE-2025-48940.
Can CVE-2025-48940 be exploited remotely?
Yes, CVE-2025-48940 can be exploited remotely if the attacker can manipulate the required parameters.