The Diffie-Hellman (DH) Group Exchange for the Secure Shell (SSH)
transport-layer protocol specifies that servers and clients should
support groups with a minimum modulus group size of 1024 bits.
Recent security research has shown that the minimum value of 1024
bits is insufficient to protect against state-sponsored actors and
any organization with enough computing resources. This RFC updates
RFC 4419, which allowed for DH moduli less than 2048 bits; now, 2048
bits is the minimum acceptable group size.
This document is a product of the CURves, Deprecating and a Little more Encryption Working Group of the IETF.
This is now a Proposed Standard.
STANDARDS TRACK: This document specifies an Internet Standards Track
protocol for the Internet community, and requests discussion and suggestions
for improvements. Please refer to the current edition of the Official
Internet Protocol Standards (https://www.rfc-editor.org/standards) for the
standardization state and status of this protocol. Distribution of this
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