CVE-2010-4011 in Mac OS X
Summary
by MITRE
Dovecot in Apple Mac OS X 10.6.5 10H574 does not properly manage memory for user names, which allows remote authenticated users to read the private e-mail of other persons in opportunistic circumstances via standard e-mail clients accessing a user s own mailbox, related to a "memory aliasing issue."
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Analysis
by VulDB Data Team • 10/05/2021
This vulnerability in Dovecot running on Apple Mac OS X 10.6.5 represents a critical memory management flaw that enables authenticated attackers to access unauthorized email content through a memory aliasing issue. The vulnerability specifically affects the handling of user names within Dovecot's memory allocation mechanisms, creating a condition where memory addresses can be incorrectly shared between different user contexts. This memory aliasing problem occurs when the system fails to properly isolate memory segments associated with different user identities, allowing a malicious user to potentially read another user's private email messages through standard email client access to their own mailbox.
The technical implementation of this vulnerability stems from improper memory management practices within Dovecot's authentication and mailbox access handling processes. When users authenticate to the email system, the application allocates memory buffers for user identification and session management. However, the flawed memory allocation logic does not adequately ensure that memory addresses remain properly isolated between different user sessions, creating opportunities for information leakage. This issue is particularly concerning because it operates within the standard email client access patterns, making exploitation relatively straightforward for authenticated users who understand the system's memory behavior.
The operational impact of this vulnerability extends beyond simple information disclosure, as it represents a fundamental breakdown in the security model of the email system. Attackers can leverage this memory aliasing issue to conduct opportunistic attacks where they access other users' email content without requiring additional privileges or complex exploitation techniques. The vulnerability is particularly dangerous in environments where multiple users share the same email server or when users have access to shared mailboxes. The fact that this issue occurs during normal email client operations means that legitimate users may inadvertently expose sensitive information to unauthorized parties.
Security professionals should recognize this vulnerability as a memory safety issue that aligns with CWE-121, which describes "Stack-based Buffer Overflow" conditions that can lead to memory corruption and information disclosure. The flaw also relates to ATT&CK technique T1005, "Data from Local System," as it enables unauthorized access to stored email data through memory manipulation. Organizations should implement immediate mitigations including updating to patched versions of Dovecot, implementing stricter memory isolation policies, and monitoring for unusual access patterns that might indicate exploitation attempts. Additionally, system administrators should consider implementing network segmentation and access controls to limit the potential impact of such vulnerabilities, while also ensuring that email server configurations properly enforce user authentication and authorization boundaries to prevent cross-user memory access scenarios.