In Ceph before 12.2.3 and 13.x through 13.0.1, the rgw_civetweb.cc RGWCivetWeb::init_env function in radosgw doesn't handle malformed HTTP headers properly, allowing for denial of service.
The handle_command function in mon/Monitor.cc in Ceph allows remote authenticated users to cause a denial of service (segmentation fault and ceph monitor crash) via an (1) empty or (2) crafted prefix.