The excerpt from the latest Travis CI job:
Fuzzing harnesses lacking a seed corpus: autofile banman buffered_file crypto_aes256 crypto_aes256cbc crypto_chacha20 crypto_chacha20_poly1305_aead crypto_hkdf_hmac_sha256_l32 crypto_poly1305 load_external_block_file policy_estimator_io
Please consider adding a fuzz seed corpus at https://github.com/bitcoin-core/qa-assets