CVE-2026-80086 in Office
Summary
by MITRE • 09/09/2026
Out-of-bounds read 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 presentation rendering engine of Microsoft Office PowerPoint, specifically categorized as an out-of-bounds read error. This type of memory corruption issue arises when the application attempts to access data stored in memory locations that are outside the boundaries of allocated buffers or arrays. In the context of PowerPoint, this typically occurs during the parsing and processing of complex slide elements, such as embedded objects, animations, or specific file formats like PPTX files containing malformed content. When an attacker crafts a malicious document with specially constructed data structures, they can trigger the application to read memory addresses that do not belong to the intended buffer. This deviation from expected program flow allows for the leakage of sensitive information residing in adjacent memory spaces, which may include credentials, encryption keys, or other proprietary data held by the user at the time of execution.
From a technical perspective, this vulnerability aligns with Common Weakness Enumeration (CWE) identifier CWE-125, known as Out-of-bounds Read. The root cause lies in insufficient validation checks performed on input parameters before they are used to calculate memory offsets or array indices. Instead of verifying that the requested index falls within the valid range of the buffer's size, the software proceeds with the read operation. This lack of boundary checking is a classic example of improper input validation, which remains one of the most prevalent categories of vulnerabilities in complex software systems like office suites. The flaw does not necessarily require code execution to be exploited for its primary impact; rather, it serves as an information disclosure vector that can facilitate further attacks or reveal internal system states that should remain hidden from untrusted sources.
The operational impact of this vulnerability is primarily centered on confidentiality loss. An unauthorized attacker who successfully exploits this condition over a network can disclose sensitive information to themselves without needing elevated privileges on the target machine. This capability undermines the trust users place in office applications, as opening a seemingly innocuous presentation file could result in the exfiltration of private data. In enterprise environments, where PowerPoint files are frequently shared via email or collaboration platforms, this risk is amplified because it can be triggered remotely without user interaction beyond simply viewing the malicious document. The ability to read arbitrary memory contents may also aid attackers in bypassing security mitigations such as Address Space Layout Randomization (ASLR) by leaking pointer addresses that reveal base load modules, thereby paving the way for more severe exploits like remote code execution.
To mitigate this risk, organizations must ensure that all Microsoft Office components are updated to the latest versions containing the necessary patches addressing these memory safety issues. Security administrators should enforce strict policies regarding the opening of files from untrusted sources and consider enabling Protected View by default, which isolates potentially dangerous documents in a sandboxed environment before allowing full access. Additionally, implementing network segmentation and monitoring for unusual data exfiltration patterns can help detect exploitation attempts early. From a development standpoint, this incident reinforces the importance of rigorous memory safety practices, including bounds checking during array accesses and adopting safer programming languages or static analysis tools that can identify such vulnerabilities prior to deployment. The ATT&CK framework classifies this behavior under techniques related to Collection via Input Capture or potentially T1059 Command and Scripting Interpreter if it leads to further exploitation, highlighting the need for comprehensive endpoint detection and response strategies to monitor for anomalous memory access patterns associated with office application abuse.