Reproduction testcase (uses PlayReady): https://developers.canal-plus.com/rx-player/upc/?appTileLocation=[object%20Object] In test streams we are using PIFF box, but caps did not had present GST_PROTECTION_SYSTEM_ID_CAPS_FIELD. In consequence, invalid system_id was returned which caused SIGSEGV crash. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3535>