How I Discovered a Complete CSRF Protection Bypass on a Major Crypto Exchange And What Happened Next
This title could be clearer and more informative.Try out Clickbait Shieldfor free (5 uses left this month).
A bug bounty researcher discovered a complete CSRF protection bypass on a major crypto exchange's Django-based admin panel. The vulnerability stemmed from the server validating CSRF tokens only by format and length (32 characters) rather than cryptographically verifying them against Django's SECRET_KEY. Any matching 32-character string in both the cookie and form field would bypass protection across all POST endpoints. Despite the critical nature of the flaw, the company classified it as out-of-scope under a 'Login CSRF' exclusion and paid only a $50 goodwill bounty. Key lessons include reading program scope carefully, distinguishing login CSRF from a complete CSRF bypass, demonstrating impact beyond the login endpoint, and ensuring Django apps use cryptographic token validation tied to SECRET_KEY.
Table of contents
IntroductionThe TargetUnderstanding CSRF — The BasicsThe DiscoveryWhy Does This Happen?Testing Multiple Arbitrary StringsThe Real-World ImpactGet Hacker MD ’s stories in your inboxReporting the VulnerabilityThe Outcome — The Hard LessonWhat I LearnedTechnical Takeaway — How Django CSRF Should WorkFinal ThoughtsSort: