winVerifyTrust is crushed when the sys time is not accurate

Question

I am developing a C# .net 3.5 application. I am trying to verify a file signature by using WinVerifyTrust. I also want a revocation check so I set the following parametrs of the WinTrustData.

    FdwRevocationChecks = WTD_REVOKE_WHOLECHAIN;
DwProvFlags = WTD_REVOCATION_CHECK_CHAIN;

everyting works OK except when I move the system time forward, then the method is stuck and winVerifyTrust return an answer only after a very long while.

Do you have any idea why it is happening and how can I prevent it?

Thanks

Answer 1

This might be happening since revocation information, whether CRL or OCSP has a thisUpdate field which tells when the revocation information becomes valid. The OS might have downloaded the revocation information and has to block till the time it becomes valid for use.