Description

Stack-based buffer overflow in Microsoft Office Access allows an unauthorized attacker to execute code locally.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-08-11T17:18:53.207Z",
  "pubdate": "2026-08-11T17:18:53.207Z",
  "executiveSummary": "A stack-based buffer overflow vulnerability has been identified in Microsoft Office Access, posing significant risk to system integrity and confidentiality. This security flaw enables an unauthorized, local attacker to achieve arbitrary code execution on targeted systems.\nThe vulnerability resides within the memory management mechanisms of the application when processing specific data structures. By leveraging this flaw, a malicious actor can cause memory corruption, resulting in the potential execution of arbitrary payloads under the security context of the currently logged-in user.\nSuccessful exploitation requires local access to the target host and relies on the victim interacting with a maliciously crafted file or input processed by Microsoft Office Access. No authentication or elevated privileges are initially required to stage the attack vector, provided the attacker can execute code locally or deliver the exploit payload to the local system.\nThe risk implications are severe, as arbitrary code execution allows attackers to subvert application controls, potentially leading to complete system compromise, unauthorized data exfiltration, or lateral movement within the affected environment.\nOrganizations utilizing Microsoft Office Access must prioritize remediation efforts, apply vendor-supplied patches when available, and implement robust endpoint monitoring to detect anomalous application behavior indicative of exploitation attempts.",
  "technicalDetails": "The vulnerability is classified as a stack-based buffer overflow affecting Microsoft Office Access. This type of memory corruption flaw occurs when the application fails to adequately validate the bounds of input data prior to copying it into a fixed-size memory buffer allocated on the call stack.\nRoot Cause Analysis: The underlying defect stems from insufficient length checks and boundary enforcement during the parsing of specific file formats or data streams handled by Microsoft Office Access. When the application ingests inputs exceeding the allocated buffer capacity, the surplus data overflows adjacent stack memory regions, typically overwriting critical structural data such as saved frame pointers and return addresses.\nAttack Vector and Flow: Exploitation of this vulnerability requires the attacker to supply a specially crafted input file or trigger a malicious data processing sequence within Microsoft Office Access. The step-by-step attack flow typically proceeds as follows: First, the attacker crafts a malicious file containing oversized payload data designed to breach memory buffer boundaries. Second, the victim opens or processes this file using a vulnerable version of Microsoft Office Access. Third, the application attempts to parse the malformed data without performing adequate bounds checking, causing the input to overflow the destination stack buffer. Fourth, the memory corruption overwrites the function's return address on the stack with a manipulated pointer controlled by the attacker. Finally, when the affected function executes its return instruction, execution flow is redirected to attacker-supplied shellcode or redirected via Return-Oriented Programming (ROP) chains.\nPrivilege and Exposure Requirements: The vulnerability is exploitable locally, requiring the attacker to either have interactive access to the host or trick a local user into opening the malicious file. Authentication is not required against a remote service, as the attack surface is exposed through local file handling and data parsing mechanisms.\nPayload Behavior and Impact: Upon successful redirection of the instruction pointer, the arbitrary payload executes with the privileges of the user running Microsoft Office Access. This post-exploitation capability allows the adversary to perform unauthorized actions, deploy persistent malware, escalate privileges if local weaknesses exist, or access sensitive databases and system resources."
}