RFC 6151 · INFORMATIONAL · 2011
WED · 29 JUL 2026
Updated Security Considerations for the MD5 Message-Digest and the HMAC-MD5 Algorithms
Overview
RFC 6151, “Updated Security Considerations for the MD5 Message-Digest and the HMAC-MD5 Algorithms”, is an Informational document published in March 2011 by S. Turner, L. Chen. It updates RFC 1321, RFC 2104. The canonical text is published by the RFC Editor.
Abstract
This document updates the security considerations for the MD5 message digest algorithm. It also updates the security considerations for HMAC-MD5. This document is not an Internet Standards Track specification; it is published for informational purposes.
What “Informational” means
Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.
Read this RFC
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