CVE-2011-2016 in Windows
Summary
by MITRE
Untrusted search path vulnerability in Windows Mail and Windows Meeting Space in Microsoft Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 allows local users to gain privileges via a Trojan horse DLL in the current working directory, as demonstrated by a directory that contains a .eml or .wcinv file, aka "Windows Mail Insecure Library Loading Vulnerability."
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Analysis
by VulDB Data Team • 06/04/2025
This vulnerability resides in the Windows Mail and Windows Meeting Space components of Microsoft Windows operating systems, specifically affecting Windows Vista SP2, Windows Server 2008 SP2 and R2, and Windows 7 Gold and SP1 versions. The core issue manifests as an untrusted search path vulnerability that enables local attackers to escalate privileges through malicious DLL loading techniques. The vulnerability operates by exploiting the insecure library loading mechanism where the applications fail to properly validate the source of dynamically loaded libraries, creating a path traversal opportunity for malicious actors to inject unauthorized code.
The technical flaw stems from the applications' failure to implement proper security controls when resolving dynamic link library dependencies. When processing .eml email files or .wcinv meeting invitation files, Windows Mail and Windows Meeting Space search for required DLL libraries in the current working directory before checking system directories. This behavior creates a predictable attack vector where an attacker can place a malicious DLL with the same name as a legitimate system library in the same directory as the targeted file. The operating system's dynamic linker will load the malicious DLL from the current directory instead of the secure system location, effectively executing attacker-controlled code with the privileges of the victim process.
The operational impact of this vulnerability is significant as it allows local users to achieve privilege escalation from standard user level to system level access. Attackers can leverage this weakness by placing malicious DLL files in directories containing .eml or .wcinv files, then tricking users into opening these files either through social engineering or by manipulating the file association process. The vulnerability is particularly dangerous because it operates silently without requiring user interaction beyond opening the malicious file, and the attack can be executed from any directory where the user has write permissions. This creates a persistent threat vector that can be exploited across multiple system components and user sessions.
Mitigation strategies should focus on implementing proper security controls including enabling Windows Defender Application Control or AppLocker policies to restrict DLL loading from untrusted directories. System administrators should also ensure that users have minimal privileges and that file system permissions are properly configured to prevent unauthorized DLL placement. The principle of least privilege should be enforced by configuring applications to only load libraries from trusted system directories and implementing strict path validation mechanisms. Additionally, regular security updates and patches from Microsoft should be applied immediately to address the root cause of the vulnerability, as this issue represents a classic example of insecure library loading that aligns with CWE-427 and CWE-428 weakness classifications. Organizations should also implement monitoring solutions to detect suspicious DLL loading activities and consider network segmentation to limit the potential impact of successful exploitation attempts.