[higherpurpose]

The same VPNs that use weak DHE crypto?

https://weakdh.org/

[juliangoldsmith]

Just use IKEv2, and you won't be affected. Or just don't use MODP1024.

[icebraining]

An even simpler approach would be to connect both ends with spiped: http://www.tarsnap.com/spiped.html