Possible crypto backdoor in RFC-2631 Diffie-Hellman Key Agreement Method

[Georgi Guninski]

Observe that reusage of group parameters in DH appears common:

Imperfect Forward Secrecy: How Diffie-Hellman Fails in Practice

https://weakdh.org/imperfect-forward-secrecy-ccs15.pdf
p.3

Table 1: Top 512-bit DH primes for TLS. 8.4% of Alexa
Top 1M HTTPS domains allow DHE_EXPORT, of which
92.3% use one of the two most popular primes, shown here.