Update SECURITY.md

Signed-off-by: Per Ploug <[email protected]>

Author: perploug

SECURITY.md

@@ -1 +1,8 @@
-If you have discovered a security vulnerability, please email [email protected]
+We acknowledge that every line of code that we write may potentially contain security issues.
+We are trying to deal with it responsibly and provide patches as quickly as possible. 
+
+We host our bug bounty program on HackerOne, it is currently private, therefore if you would like to report a vulnerability and get rewarded for it, please ask to join our program by filling this form:
+
+https://corporate.zalando.com/en/services-and-contact#security-form
+
+You can also send you report via this form if you do not want to join our bug bounty program and just want to report a vulnerability or security issue.