Security assessment low severity issues

A security assessment was done ( https://github.com/ANSSI-FR/MLA/blob/f6fd585cb35b1d4caa84eaed06669b6434589e1d/doc/20260130-mla-security-assessment.pdf ) and reported some low severity issues: 1. [LOW] Incomplete memory zeroization 2. [LOW] Inappropriate default privileges on private key files 3. [REMARK] Possible initialization vector reuse if the size of data chunks is extended 4. [REMARK] Multiple integer overflows