CVE-2006-0129 in MailSite
Summary
by MITRE
Mail Management Agent (MAILMA) (aka Mail Management Server) in Rockliffe MailSite 7.0.3.1 and earlier generates different responses depending on whether or not a username is valid, which allows remote attackers to enumerate valid usernames via user requests to TCP port 106.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 01/11/2019
The vulnerability described in CVE-2006-0129 represents a classic account enumeration flaw within the Rockliffe MailSite 7.0.3.1 mail management system. This issue specifically affects the Mail Management Agent component that operates on TCP port 106, which is the standard port used for mail management services. The flaw stems from the system's inconsistent response behavior when processing user authentication requests, creating a predictable pattern that attackers can exploit to determine valid usernames within the system. This type of vulnerability falls under the category of information disclosure and credential guessing attacks, where the system inadvertently reveals information about its internal state through its response mechanisms.
The technical implementation of this vulnerability occurs at the protocol level where the MAILMA component fails to provide uniform response times or error messages regardless of whether a username exists in the system. When an attacker sends authentication requests to port 106, the system responds differently based on the validity of the username provided. Valid usernames typically generate responses that are slightly faster or contain specific error codes that differ from those generated when invalid usernames are submitted. This timing differential or response variation creates a side-channel attack vector that allows malicious actors to systematically test usernames and identify which ones are valid within the MailSite system. The vulnerability directly relates to CWE-200, which addresses information exposure through improper error handling, and also aligns with ATT&CK technique T1078 for valid accounts and T1110 for credential access.
The operational impact of this vulnerability extends beyond simple username enumeration, as it provides attackers with a foundation for more sophisticated attacks including brute force authentication attempts, dictionary attacks, and social engineering campaigns. Once valid usernames are identified, attackers can focus their efforts on cracking passwords for those specific accounts, significantly reducing the computational resources and time required for successful unauthorized access. The vulnerability affects organizations using Rockliffe MailSite 7.0.3.1 and earlier versions, potentially exposing thousands of email accounts to compromise. The impact is particularly severe in enterprise environments where email systems serve as primary communication channels and contain sensitive business data, personal information, and potentially privileged access credentials. Organizations may experience data breaches, unauthorized access to confidential communications, and potential lateral movement within their networks through compromised email accounts.
Mitigation strategies for this vulnerability require immediate attention through software updates and configuration changes. The primary solution involves upgrading to Rockliffe MailSite versions that address this specific enumeration flaw by implementing consistent response handling for all authentication attempts. System administrators should also implement rate limiting and connection throttling mechanisms to prevent automated enumeration attacks from succeeding. Network-level protections such as firewall rules can restrict access to TCP port 106 from unauthorized sources and implement monitoring for suspicious traffic patterns. Additionally, organizations should consider implementing account lockout policies and multi-factor authentication to add additional layers of security. Security teams should conduct regular vulnerability assessments and penetration testing to identify similar enumeration vulnerabilities in other mail systems and network services. The remediation process should include comprehensive logging and monitoring of authentication attempts to detect and respond to potential exploitation attempts, while also ensuring that all security patches are applied promptly to prevent similar issues in other components of the mail infrastructure.