Description

Heap-based buffer overflow in Windows GDI+ allows an authorized attacker to execute code locally.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-08-11T17:18:40.353Z",
  "pubdate": "2026-08-11T17:18:40.353Z",
  "executiveSummary": "A heap-based buffer overflow vulnerability exists in Windows GDI+, a critical graphical component of the Microsoft Windows operating system. The vulnerability allows an authorized local attacker to achieve arbitrary code execution on the target system. The flaw stems from improper memory management during the processing of image or graphical data structures within the GDI+ rendering engine. Successful exploitation of this vulnerability compromises the confidentiality, integrity, and availability of the underlying host. The risk implications are severe, as arbitrary code execution under the security context of the user process interacting with the malicious graphical asset can lead to privilege escalation or system compromise. The attacker capabilities are constrained by the requirement of local access or user interaction, such as opening a crafted image file or accessing a vulnerable application rendering malformed content. Mitigation relies on applying official security updates provided by the vendor, implementing strict input validation policies, and adhering to the principle of least privilege for local users.",
  "technicalDetails": "The vulnerability is classified as a heap-based buffer overflow residing within the Windows GDI+ component, specifically inside functions responsible for parsing and rendering specific image formats or graphical primitives. The root cause of the flaw is the lack of proper boundary checks and integer overflow validations when calculating memory allocation sizes for dynamic buffers on the heap. When the GDI+ subsystem processes a specially crafted image file containing malicious metadata or dimensions, the arithmetic operation used to determine the required buffer size results in an integer wrap-around or under-allocation. Subsequently, the parsing routine copies data exceeding the allocated heap chunk size into the destination buffer, resulting in a heap-based buffer overflow.\nThe attack flow begins when an authorized local attacker or a victim interacts with a malformed graphical file using an application that leverages the Windows GDI+ API for rendering. This can occur through local file system access, removable media, or local application execution paths. Upon parsing the malicious file structure, the vulnerable function triggers the heap corruption by writing beyond the bounds of the heap chunk. The memory corruption overwrites adjacent heap metadata, control structures, or function pointers stored within the heap space.\nBy carefully crafting the payload, an attacker can manipulate adjacent heap structures to achieve arbitrary read/write primitives or hijack the execution flow when overwritten function pointers or virtual method tables are subsequently dereferenced. The payload behavior involves redirecting execution to shellcode embedded within the heap, leading to code execution with the privileges of the running process. The vulnerability requires local access and does not expose a direct network attack vector unless combined with a secondary remote service vector that utilizes GDI+ for image processing. Authentication requirements depend on the local environment, but the attacker must possess local execution capabilities to trigger the flaw."
}