> For the complete documentation index, see [llms.txt](https://mahmoud-shaker.gitbook.io/dfir-notes/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mahmoud-shaker.gitbook.io/dfir-notes/cidsizemru.md).

# CIDSizeMRU

### **Overview:**

* **Purpose**: Tracks file dialogs in Windows Explorer, showing which files were accessed or saved using file picker dialogs.
* **Registry Location**:
  * `HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\ComDlg32\CIDSizeMRU`
* **Structure**:
  * Stores file paths and recent directory usage.

### **Benefits for DFIR:**

* **File Access Evidence**: Indicates user interaction with files and directories.
* **Behavioral Analysis**: Useful in identifying files that were recently accessed or saved.

### **How It Works:**

* Logs information about files accessed or saved through common dialog boxes, including:
  * **File Path**: Most recently accessed directories.
  * **Timestamps**: Indicates recency of usage.

### **Tools:**

* **Registry Explorer**: For manual extraction and analysis.
* **Regripper**: Automates parsing of CIDSizeMRU entries.


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