buffer.c in named in ISC BIND 9.10.x before 9.10.3-P3, when debug logging is enabled, allows remote attackers to cause a denial of service (REQUIRE assertion failure and daemon exit, or daemon crash) or possibly have unspecified other impact via (1) OPT data or (2) an ECS option.
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.