[Kindle Colorsoft] USB Mass Storage Gadget (PID 0x0324) during boot - ~0.43s window

[angerss.sykes]

Hi everyone,

I discovered something interesting on the Kindle Colorsoft (firmware 5.18.6):

## Discovery
During boot, the device briefly exposes itself as a different USB device:

**Normal mode (after boot):**
- VID: 0x1949 (Amazon)
- PID: 0x9981
- Name: "Kindle Colorsoft"

**During boot (~0.43 seconds):**
- VID: 0x1949 (Amazon)
- PID: 0x0324
- Name: "Mass Storage Gadget"
- USB Vendor String: "Linux 5.15.41-lab126 with mtu3"

## Technical details
- The Colorsoft uses a MediaTek chip (mtu3 USB driver)
- mtkclient detects it but handshake fails (window too short)
- The device appears to expose Mass Storage briefly before switching to MTP

## Questions
1. Has anyone else noticed this behavior?
2. Is there a button combination to extend this window or enter BROM mode?
3. Can this be exploited for jailbreaking?

Device info:
- Model: Kindle Colorsoft
- Firmware: 5.18.6
- Kernel: Linux 5.15.41-lab126

[mergen3107]

> 3. Can this be exploited for jailbreaking?

This can be more useful over on Kindle Modding Discord server
https://discord.gg/kindle