Treat the explanation as untrusted diagnostic text
05EDE does not authenticate itself. A malicious server or an attacker on an unprotected path can supply misleading reasons, and extra detail can expose information that did not need to leave the server.
Separate unsafe automation proposal: an EDE claim would trigger disabling DNS validation. Stop that action; applicable DNS protocol and RCODE processing MUST continue unchanged. EDE supplies context, not a new downgrade permission.
Source for this drawing: RFC 8914 · Read RFC section 6 ↗
New to this? Start hereA quick picture + helpful background
A message needs an address.
Think of a packet as a small addressed envelope. Devices pass it onward; transport protocols decide what delivery promises an application gets.
Helpful first, if these ideas are unfamiliar
These pictures are analogies to help you learn. The linked RFC explains the actual rules.
Terms in this drawing
Related RFCs and changes
“Updates” changes part of an earlier RFC. “Obsoletes” replaces it. This list shows selected related documents.
Diagnostics must not override DNS processing or become executable instructions.
- EDE is unauthenticated unless secured as part of a secured DNS transaction. Even protected transport does not prove a malicious resolver’s explanation is truthful.
- EDE content should be treated as diagnostic information and MUST NOT alter DNS protocol processing. It does not authorize disabling DNSSEC validation or overriding the normal RCODE requirements.
- EXTRA-TEXT is for human consumption, not automated parsing. The literal-text display gate is this guide’s safe-UI example, not a new normative HTML escaping rule in RFC 8914.
- The source advises care not to disclose private information such as account numbers in EXTRA-TEXT. It does not introduce a new uppercase MUST for that advice; diagnostic reasons can themselves leak policy information.
All data is fictional. The page displays examples but performs no DNS transaction, executable-text interpretation or account lookup. Full DNSSEC, transport authentication, network-text sanitization and resolver policies are separate specifications and implementations.
Read the RFC section ↗