Change PKCS12 password to assist with credscan

[vcsjones]

/cc @aik-jahoda

[ghost]

Tagging subscribers to this area: @bartonjs, @vcsjones, @krwq, @GrabYourPitchforks
See info in area-owners.md if you want to be subscribed.

Issue Details

---

/cc @aik-jahoda

Author:	vcsjones
Assignees:	-
Labels:	area-System.Security, community-contribution
Milestone:	-

[vcsjones]

Converting to draft because apparently the password was supposed to be PLACEHOLDER. Will change it again.

[bartonjs]

If we already have it suppressed, why are we changing it?

Does the new PKCS12 use the same encryption and MAC parameters, or are we possibly losing some edge coverage on DSA?

[vcsjones]

If we already have it suppressed, why are we changing it?

I got an email I should change it. I'm guessing the comment suppression wasn't enough and there maybe needed to be another above the .ctor for X509Certificate2 for the password itself.

Does the new PKCS12 use the same encryption and MAC parameters

Yes. Same PBE parameters, same key (DSA). Just changing the PBE password.

[aik-jahoda]

The problem is not in the certificate itself, but with

return new X509Certificate2(SampleDsaPfx, "velleity");

It complains about plaintext password. We decided to prefer PLACEHOLDER as a safe well known "password" which at first sight confirm it is test only password.

[aik-jahoda]

LGTM

[aik-jahoda]

/backport to release/6.0

[github-actions]

Started backporting to release/6.0: https://github.com/dotnet/runtime/actions/runs/1233560600