CVE-2001-1188 in MAILTO
Summary
by MITRE
mailto.exe in Brian Dorricott MAILTO 1.0.9 and earlier allows remote attackers to send SPAM e-mail through remote servers by modifying the sendto, email, server, subject, and resulturl hidden form fields.
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Analysis
by VulDB Data Team • 09/27/2025
The vulnerability identified as CVE-2001-1188 resides within the mailto.exe component of Brian Dorricott MAILTO version 1.0.9 and earlier, representing a significant security flaw in email submission mechanisms. This issue manifests as a remote code execution vulnerability that enables attackers to manipulate form fields to send unsolicited bulk email messages through remote servers, effectively creating a vector for spam distribution. The vulnerability stems from insufficient input validation and sanitization within the web-based email submission interface, allowing malicious actors to bypass normal email sending restrictions and potentially abuse the system for spam campaigns.
The technical implementation of this vulnerability involves manipulation of hidden form fields within the mailto.exe application, specifically targeting sendto, email, server, subject, and resulturl parameters. These fields are typically designed to be automatically populated or validated by the application, but due to inadequate security controls, attackers can directly modify these values to redirect email submissions through their own server configurations. This manipulation allows threat actors to forge email headers, specify arbitrary recipient addresses, and potentially establish relay mechanisms for spam distribution. The vulnerability operates at the application layer, specifically within web form processing and email submission workflows, making it particularly dangerous for web-based email systems that rely on user input for message routing.
The operational impact of this vulnerability extends beyond simple spam generation, as it can be leveraged for more sophisticated attack vectors including phishing campaigns, credential harvesting, and network reconnaissance. When exploited, the vulnerability enables attackers to send spam emails from compromised systems without proper authentication, potentially leading to reputation damage for the affected organization and potential blacklisting of their email servers. The vulnerability also presents a risk for abuse in distributed denial-of-service scenarios where spam emails are used as amplification vectors. According to CWE classification, this vulnerability corresponds to CWE-20: Improper Input Validation, which encompasses various forms of input sanitization failures that can lead to code injection and unauthorized system access. The attack pattern aligns with ATT&CK technique T1192: Spoof Email Address, where adversaries manipulate email headers and routing to disguise their activities and evade detection mechanisms.
Mitigation strategies for CVE-2001-1188 should focus on implementing robust input validation and sanitization controls within the mailto.exe application. Organizations should immediately upgrade to patched versions of the MAILTO software or implement web application firewalls to filter malicious form submissions. The solution requires comprehensive validation of all form fields, particularly hidden fields, with strict sanitization of user inputs to prevent parameter manipulation. Additionally, implementing proper access controls and authentication mechanisms for email submission functions can significantly reduce the attack surface. Security measures should include input length restrictions, character set validation, and regular security audits of web applications to identify similar vulnerabilities. The vulnerability also underscores the importance of proper application security design principles including defense in depth, least privilege access, and input validation at multiple layers of the application architecture to prevent similar issues from occurring in future implementations.