CVE-2026-72938 in Office
Summary
by MITRE • 09/09/2026
Access of resource using incompatible type ('type confusion') in Microsoft Office PowerPoint allows an unauthorized attacker to disclose information over a network.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability described constitutes a critical security flaw within the Microsoft Office PowerPoint application, specifically categorized as a type confusion error during resource access operations. This class of defect arises when software incorrectly assumes that a data structure or object belongs to one specific data type while it is actually another, leading to unpredictable behavior and potential exploitation by malicious actors. In this context, an unauthorized attacker can leverage the misinterpretation of memory structures to bypass intended security controls, resulting in the disclosure of sensitive information over a network. This scenario highlights a fundamental failure in input validation and type safety checks within the application's parsing engine or rendering subsystems, where external inputs are not sufficiently sanitized before being processed as specific internal object types.
From a technical perspective, this vulnerability aligns with Common Weakness Enumeration (CWE) identifiers such as CWE-843, which refers to Access of Resource Using Incompatible Type, and potentially CWE-120 or related buffer overflow variants if the type confusion leads to memory corruption that facilitates information leakage. The core issue lies in the application's inability to correctly distinguish between different object types during runtime execution. When PowerPoint processes complex documents containing embedded objects, macros, or specific formatting structures, it may allocate memory and assign pointers based on an assumed type. If a crafted file forces the application to treat data as a different type than intended, the resulting memory access patterns can expose internal state information that was not meant for external consumption. This could include sensitive user credentials, document metadata, or other proprietary data stored in adjacent memory regions due to improper boundary checks and type casting mechanisms.
The operational impact of this vulnerability is significant, particularly given the widespread use of Microsoft Office products in enterprise environments where PowerPoint files are frequently exchanged via email and network shares. An attacker who successfully exploits this flaw can achieve remote information disclosure without requiring user interaction beyond opening a maliciously crafted file or visiting a compromised webpage that triggers automatic rendering. This capability allows for stealthy data exfiltration, as the attack vector operates over standard network protocols such as HTTP or HTTPS, making it difficult to detect through traditional perimeter security measures. The ability to disclose information remotely increases the risk profile substantially, as it transforms what might otherwise be a local privilege escalation issue into a widespread remote code execution precursor or direct confidentiality breach affecting multiple users simultaneously.
Mitigation strategies for this vulnerability must focus on both immediate remediation and long-term architectural improvements. Organizations should immediately apply the latest security patches released by Microsoft to update PowerPoint and related Office components, ensuring that type checking logic is corrected in the affected versions. Additionally, implementing application whitelisting policies can restrict the execution of untrusted scripts or macros within Office applications, thereby reducing the attack surface for exploitation attempts. Network segmentation and strict e-mail filtering rules should also be enforced to prevent malicious files from reaching end-user systems. From a development standpoint, enforcing stricter type safety checks during code review and utilizing static analysis tools that detect potential type confusion errors can help prevent similar vulnerabilities in future software releases. Adhering to secure coding standards such as those outlined by the OWASP Top Ten for input validation and output encoding will further harden applications against these classes of defects.