CVE-2007-2223 in XML Core Services
Summary
by MITRE
Microsoft XML Core Services (MSXML) 3.0 through 6.0 allows remote attackers to execute arbitrary code via the substringData method on a (1) TextNode or (2) XMLDOM object, which causes an integer overflow that leads to a buffer overflow.
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Analysis
by VulDB Data Team • 01/13/2025
Microsoft XML Core Services MSXML versions 3.0 through 6.0 contain a critical vulnerability in the substringData method implementation that affects both TextNode and XMLDOM objects. This vulnerability stems from improper integer overflow handling during string manipulation operations, creating a condition where malicious input can cause arithmetic overflow leading to buffer overflow conditions. The flaw occurs when the substringData method processes user-supplied data that exceeds the bounds of allocated memory buffers, allowing attackers to manipulate memory layout and execute arbitrary code with the privileges of the affected application.
The technical implementation of this vulnerability involves the manipulation of integer values within the MSXML parsing engine where the substringData method fails to properly validate input parameters before performing arithmetic operations. When an attacker supplies a carefully crafted integer value that causes overflow during the calculation of buffer boundaries, the system allocates insufficient memory space for the resulting string operation. This integer overflow condition directly translates to a buffer overflow scenario where subsequent memory operations can overwrite adjacent memory regions, potentially including stack canaries, return addresses, or other critical program data structures. The vulnerability is particularly dangerous because it operates within the core XML processing functionality that many applications rely upon for parsing user input, making it a prime target for exploitation in web-based attack scenarios.
From an operational standpoint, this vulnerability presents significant risk to systems running affected MSXML versions as it enables remote code execution without requiring user interaction or authentication. Attackers can craft malicious XML documents containing specially formatted substringData method calls that trigger the overflow condition when processed by vulnerable applications. The exploitation typically follows a pattern where the attacker constructs XML content with oversized parameters that cause the integer overflow, leading to controlled memory corruption. This vulnerability affects not only Microsoft's own applications but also third-party software that depends on MSXML for XML processing, creating widespread potential impact across enterprise environments. The vulnerability aligns with CWE-190, Integer Overflow or Wraparound, and maps to ATT&CK technique T1203, Exploitation for Client Execution, as it enables remote code execution through client-side XML processing.
Mitigation strategies for this vulnerability include immediate deployment of Microsoft security patches that address the integer overflow condition in the substringData method implementation. Organizations should prioritize updating all systems running MSXML 3.0 through 6.0 to the latest security updates from Microsoft, as the vulnerability has been fully addressed in subsequent releases. Additionally, network administrators should implement XML input validation and sanitization measures at application boundaries to prevent malicious XML content from reaching vulnerable MSXML components. Input validation should specifically target XML documents containing substringData method calls with suspicious parameter values that could trigger integer overflow conditions. Security monitoring should include detection of unusual XML processing patterns that might indicate exploitation attempts. The vulnerability also highlights the importance of application sandboxing and privilege separation to limit the potential impact of successful exploitation, as the code execution would occur within the context of the MSXML processing application. Organizations should also consider implementing web application firewalls that can detect and block malicious XML content before it reaches vulnerable applications.