This affects the package com.softwaremill.akka-http-session:core_2.12 from 0 and before 0.6.1; all versions of package com.softwaremill.akka-http-session:core_2.11; the package com.softwaremill.akka-http-session:core_2.13 from 0 and before 0.6.1. CSRF protection can be bypassed by forging a request that contains the same value for both the X-XSRF-TOKEN header and the XSRF-TOKEN cookie value, as the check in randomTokenCsrfProtection only checks that the two values are equal and non-empty.