SSL certificate cannot be trusted

[Harish_Sankaran]

• We got "SSL certificate cannot be trusted" vulnerability in the tool scanner.
• We are running the R77.30 in proxy.

I need solution for this vulnerability.

[PhoneBoy]

An untrusted certificate is not necessarily a vulnerability, it just means your scanner can't validate the certificate it encountered.
If, for example, it was for the Gaia Portal, which by default uses a self-signed certificate, this is expected behavior.
Without knowing where it exactly encountered this untrusted certificate, I can't tell you how to replace it with a trusted one.