You need clarification on whether Symantec Endpoint Protection (SEP) and its email plug-ins contain an anti-phishing product component.

SEP is not intended to be an Anti-Phishing product.  Phishing is within the domain of AntiSpam and Mail Security products. 

SEP does have a number of IPS signatures which can provide a small extra degree of protection against phishing sites and traffic, but these IPS signatures are one last layer of a "defense in depth" and should not be relied upon to alone defend against phishing. 

• HTTP Ninja Phishing Kit Activity
• Web Attack: Malicious Phishing Request
• Web Attack: Malicious Phishing Request 2

Phishing mails work by social engineering their recipients into clicking a link and taking harmful actions.  They are not malicious code. Please submit any missed phishing mails to your AntiSpam vendor rather than to the site for suspected missed malware.  Any phishing materials accidentally submitted to the portal "Upload a suspected infected file" will be closed off as Threat artifact (or similar).  Links in any mails (and their .pdf attachments) will not be examined.  Additional information can be found in Symantec Insider Tip: Successful Submissions!

Some useful resources:

• Symantec Guide to Scary Internet Stuff - Phishing
  https://www.youtube.com/watch?v=v3JGY2L8NK4 (Tip: search YouTube for it if the link is no longer valid)
   
• Why Phishing Continues to Spear Victims
  https://www.symantec.com/blogs/expert-perspectives/why-phishing-continues-spear-victims
   
• The phishing economy: How phishing kits make scams easier to operate
  https://www-secure.symantec.com/connect/blogs/phishing-economy-how-phishing-kits-make-scams-easier-operate
   
• How to Take Protection Against Phishers Up a Notch
  https://www.symantec.com/blogs/product-insights/how-take-protection-against-phishers-notch
  .
• Security Response's monthly threat intelligence report contains news on trends in phishing and spam.