AIKIDO-2026-916437

TL;DR

c-ares allocates resource record arrays from the answer, authority, and additional counts in the DNS header before checking that the message holds those records. A 12 byte header that sets each count to 65535 forces a multi megabyte allocation that is released when the parse fails. A stream of those responses puts pressure on the allocator and can stall resolution. The fix rejects a record count that cannot fit in the remaining bytes before it allocates.