Description

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

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.4",
  "pubDate": "2026-08-11T17:19:07.653Z",
  "pubdate": "2026-08-11T17:19:07.653Z",
  "executiveSummary": "This vulnerability is classified as a heap-based buffer overflow affecting Microsoft Office.\nThe security flaw enables an unauthorized local attacker to execute arbitrary code within the context of the user running the vulnerable application.\nThe affected product is Microsoft Office, which handles memory management inadequately when parsing specific inputs, leading to memory corruption.\nRisk implications are severe, as successful exploitation may result in complete system compromise, unauthorized data access, and persistent local execution.\nAttacker capabilities require local access to the target system to initiate the attack sequence, typically by tricking a user into opening a maliciously crafted file.\nExploitation requirements include local execution context and user interaction to process the malicious input vector within Microsoft Office.",
  "technicalDetails": "The vulnerability stems from a heap-based buffer overflow flaw located within the memory management routines of Microsoft Office.\nThe root cause involves insufficient bounds checking when processing complex data structures or parsing specific file formats.\nWhen a specially crafted file is opened by the application, the vulnerable component allocates an inadequate amount of heap memory for incoming data.\nWriting data past the allocated heap buffer boundary overwrites adjacent heap metadata, function pointers, or critical application objects.\nAn unauthorized local attacker leverages this memory corruption state to hijack the application control flow.\nThe attack flow begins with the delivery of the malicious file to the local system, followed by the victim opening the file using Microsoft Office.\nThe parsing engine encounters the malformed data structure, triggers the heap-based buffer overflow, and corrupts adjacent heap structures.\nPost-exploitation impact includes the execution of arbitrary shellcode or payload behavior determined by the attacker, inheriting the privileges of the locally logged-in user.\nAuthentication requirements are absent for the initial local execution phase, and exploitation relies entirely on local file handling mechanisms.\nThe vulnerability highlights deficiencies in secure memory handling and input validation routines within the core parsing components of Microsoft Office."
}