TLS Alert Codes

Numeric alert codes transmitted in TLS Alert messages, as defined in RFC 8446 (TLS 1.3) and earlier TLS/SSL specifications. Alert codes indicate why a connection is being terminated or notify the peer of a condition.

34 codes

• access_denied access_denied
• bad_certificate bad_certificate
• bad_certificate_hash_value bad_certificate_hash_value
• bad_certificate_status_response bad_certificate_status_response
• bad_record_mac bad_record_mac
• certificate_expired certificate_expired
• certificate_required certificate_required
• certificate_revoked certificate_revoked
• certificate_unknown certificate_unknown
• certificate_unobtainable certificate_unobtainable
• close_notify close_notify
• decode_error decode_error
• decompression_failure decompression_failure
• decrypt_error decrypt_error
• decryption_failed_RESERVED decryption_failed_RESERVED
• export_restriction_RESERVED export_restriction_RESERVED
• handshake_failure handshake_failure
• illegal_parameter illegal_parameter
• inappropriate_fallback inappropriate_fallback
• insufficient_security insufficient_security
• internal_error internal_error
• missing_extension missing_extension
• no_application_protocol no_application_protocol
• no_certificate_RESERVED no_certificate_RESERVED
• no_renegotiation_RESERVED no_renegotiation_RESERVED
• protocol_version protocol_version
• record_overflow record_overflow
• unexpected_message unexpected_message
• unknown_ca unknown_ca
• unknown_psk_identity unknown_psk_identity
• unrecognized_name unrecognized_name
• unsupported_certificate unsupported_certificate
• unsupported_extension unsupported_extension
• user_canceled user_canceled