Microsoft on Tuesday acknowledged the existence of exploit code that could crash vulnerable Windows computers through a flaw in image file handling. The company had provided a patch for the problem as part of its November Patch Tuesday security update.

The flaw affects the way the OS renders Windows Metafile and Enhance Metafile image formats. While the vulnerability could lead to remote code execution, Microsoft says that, based on its research, this particular exploit would only cause a denial of service attack. So far, the company has not been made aware of any reported attacks using the code.