You might have to use the Firepower Management Center (FMC), which is the tool that allows you to create and manage custom signatures for Firepower devices. Here are the steps to do it:
- Log in to the FMC web interface and go to Objects > Object Management > Intrusion Rules.
- Select the custom signature that you want to export and click Edit.
- In the Edit Intrusion Rule window, click Advanced and then click View Snort Rule.
- A new window will open with the SNORT rule syntax for the custom signature. You can copy and paste it to a text file or use the Download Snort Rule button to save it as a file.
- Repeat these steps for any other custom signatures that you want to export.
