Private Key Exposure or Private Key Compromise

I found RSA private key: -----BEGIN RSA PRIVATE KEY----- found in https://cyberchef.org/assets/main.js

Start by inspecting the deployed https://cyberchef.org/assets/main.js and searching the repository or build inputs for the reported RSA private-key material. Determine whether the key is genuinely exposed and identify the affected asset or source. Done means the exposure and required remediation are confirmed and documented.

Written by the indexing model from the issue text.