You want to check Symantec Network Security products Security Advisory for CVE/Vulnerabilities. This includes Edge SWG(ProxySG), Cloud SWG, SSLV, CAS, Management Center, etc.
You can search the Security Advisories for CVE's and Vulnerabilities using this link.
Security Advisory: (You want to know if a Symantec Network Security product is impacted by one or more vulnerabilities documented in a security advisory.)
CVE Assessment: (You want more detail about a CVE in the context of a specific Symantec Network Security product.)
Vulnerability Scan Result: (A vulnerability scanner indicates Symantec Network Security product is impacted by a particular vulnerability.)
Customer Reported Vulnerability: (You are reporting a new vulnerability.)
PSIRT maintains the following public facing page with instructions for an external researcher to submit suspected product security issues to Symantec.
If you believe you have found a vulnerability in a Symantec product, cloud service, or IT infrastructure that has not been resolved, please contact Symantec via the email addresses provided below: