Hi,

we have recently discovered a vulnerability in the VSIX Installer of Visual Studio. More specifically, the vulnerability existed in the validation of VSIX package signatures. This vulnerability allowed attackers

*        to 'revive' expired code-signing certificates for VSIX package signatures and

*        to maliciously modify timestamps when intercepting timestamp requests for VSIX package signatures.

For more details see here:
https://about.signpath.io/blog/2020/08/26/on-the-importance-of-trust-validation.html

Best regards,
SignPath