Description

Untrusted pointer dereference in Microsoft Office allows an unauthorized attacker to execute code locally.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-08-11T17:18:52.137Z",
  "pubdate": "2026-08-11T17:18:52.137Z",
  "executiveSummary": "An untrusted pointer dereference vulnerability exists within Microsoft Office, posing significant security risks to affected systems. This vulnerability allows an unauthorized local attacker to execute arbitrary code within the context of the current user. The flaw stems from improper handling of memory pointers by the affected software component when processing untrusted input or document structures. Successful exploitation requires the attacker to have local access to the target system and typically involves tricking a user into opening a specially crafted malicious file using the vulnerable Microsoft Office application. The potential impact of successful code execution includes complete system compromise, unauthorized data access, modification, or deletion, and the installation of persistent malware or backdoors. Because the vulnerability enables local code execution without prior authentication, organizations face heightened risks of lateral movement and privilege escalation if an initial foothold is established via social engineering or compromised local vectors. Remediation efforts should focus on applying official vendor patches as soon as they become available and enforcing strict security controls regarding the execution of untrusted documents.",
  "technicalDetails": "The vulnerability is characterized as an untrusted pointer dereference occurring within the memory management routines of Microsoft Office. The root cause lies in the application's failure to properly validate and sanitize memory pointers derived from external or untrusted data sources before dereferencing them. When a vulnerable Microsoft Office component parses a specially crafted file, it encounters a corrupted or manipulated memory address that does not point to valid, expected object structures. Because the application blindly trusts the offset or pointer value without performing adequate bounds checking or type validation, a dereference operation occurs on an arbitrary or controlled memory location.\nThe exploitation method relies on manipulating the application's internal memory state to achieve arbitrary code execution. An attacker crafts a malicious document designed to exploit this improper pointer handling. Upon opening the file, the vulnerable component processes the malicious structure, leading to a read or write operation at an unintended memory address. This condition can be leveraged to corrupt critical application data structures, manipulate function pointers, or redirect the execution flow to attacker-supplied shellcode or Return-Oriented Programming (ROP) chains residing in memory.\nThe attack flow proceeds as follows: First, the unauthorized attacker delivers a malicious file to the target machine via local methods, removable media, or social engineering. Second, the user opens the file using the vulnerable Microsoft Office application. Third, the parsing engine processes the malformed structures, triggering the untrusted pointer dereference. Fourth, the improper memory dereference alters the control flow of the application. Finally, the attacker achieves arbitrary code execution with the privileges of the locally logged-in user, allowing for post-exploitation activities such as payload deployment, credential harvesting, and further system compromise. The vulnerability requires local access, and exploitation is typically contingent upon user interaction in the form of opening the malicious document."
}