In the early releases, 2.9.9 through 3.7, other than 1024, the DH moduli were "off by 1". Starting with 3.8, it got addressed.
Starting with 6.9, released July 2015, 1024-bit DH primes were dropped. This is likely due to the Logjam vulnerability, which was announced May 2015.
With 7.3, the minimum DH modulus bit size is now 2048 bits.
Also, not a problem, but the bit sizes aren't always a multiple of powers of 2. But other than prior to 3.8, they are multiples of 512.
https://gist.github.com/atoponce/3e9818de651e5f87d911dc2d1f7e8380
Aaron Toponce ⚛️:debian:
npub1t9…t8529
2025-02-26 19:40:27 UTC
in reply to nevent1q…x3yj
Author Public Key
npub1t9cz9v7zph5jvadd8rjfp25msrx6r0hdxnsyfmx88k8qp3pvv04szt8529Published at
2025-02-26 19:40:27 UTCEvent JSON
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"content": "In the early releases, 2.9.9 through 3.7, other than 1024, the DH moduli were \"off by 1\". Starting with 3.8, it got addressed.\n\nStarting with 6.9, released July 2015, 1024-bit DH primes were dropped. This is likely due to the Logjam vulnerability, which was announced May 2015.\n\nWith 7.3, the minimum DH modulus bit size is now 2048 bits.\n\nAlso, not a problem, but the bit sizes aren't always a multiple of powers of 2. But other than prior to 3.8, they are multiples of 512.\n\nhttps://gist.github.com/atoponce/3e9818de651e5f87d911dc2d1f7e8380",
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