jtcsec has reached Level 4 with 75+ unique vulnerabilities discovered and they have proven to us that they understand web application vulnerabilities and how to discover them. If you run a bug bounty/vulnerability disclosure program and you are looking for an active, professional researcher, we recommend checking out jtcsec's bug bounty platform information below and to consider inviting them.
Connected Bug Bounty Platforms
HackerOne: jtcsec 10 submissions
Bugcrowd: jtcsec 2 submissions
Intigriti: jtcsec 2 submissions
Disclosed Bugs (On HackerOne)