cannot import PKCS12

Problem Description

PKCS12 ask for password.

Steps to reproduce the behavior:

1. http://mitm.it/#Windows
2. Download Certificate
3. Open
4. Click Next
5. Error

System Information

Mitmproxy: 12.2.3 binary
Python:    3.14.4
OpenSSL:   OpenSSL 3.5.5 27 Jan 2026
Platform:  Windows-10-10.0.19045-SP0

Checklist

• This bug affects the latest mitmproxy release.

Workaround

I added the Cert Certificate instead (linux pem, split cert/key, and add the cert file).