CyberRota Analysis
AI-GeneratedMyBB forum software versions prior to 1.8.40 are vulnerable due to improper sanitization of sender names in the Email User controller, which can lead to mail header injection via the fromname HTTP parameter. This vulnerability allows attackers to inject arbitrary headers into the Return-Path and Reply-To fields, potentially facilitating phishing attacks or email spoofing. Organizations using affected MyBB versions should prioritize upgrading to 1.8.40 to mitigate this risk.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
MyBB is free and open source forum software. Prior to 1.8.40, the Email User controller does not sanitize sender names correctly, resulting in mail header injection. member.php?action=do_emailuser accepts the fromname HTTP parameter for guests or the stored username for authenticated users when the cansendemail group permission is enabled. When mail_handler is set to the default PHP mail value, the sender name is used without sanitization in Return-Path and Reply-To headers, allowing arbitrary headers to be injected with CRLF sequences. This issue is fixed in version 1.8.40.