Epoxy and fiberglass can be used to successfully repair hull and deck cracks.
There are some important steps to follow, and the correct materials must be used.

Epoxy resin bonds very well to many materials, including kayaks made of ABS, fiberglass, and epoxy resins.

Youtube user Mark Jones shares his experience:

Hurricane brand kayaks are repaired with epoxy and fiberglass. A final gel goat application makes the repair disappear.