// For flags

CVE-2025-48940

MyBB's upgrade component vulnerable to local file inclusion

Severity Score

7.2
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

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.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
High
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
Multiple
Confidentiality
Complete
Integrity
Complete
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2025-05-28 CVE Reserved
  • 2025-06-02 CVE Published
  • 2025-06-02 CVE Updated
  • 2025-06-08 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Mybb
Search vendor "Mybb"
 Mybb
Search vendor "Mybb" for product "Mybb"
 < 1.8.39
Search vendor "Mybb" for product "Mybb" and version " < 1.8.39"
en
Affected