[goblin89]

Keybase Teams—also featuring e2e-encrypted group chat—appears to be proof against the ghost-user-based attack.

It would be interesting to compare its implementation to how Signal does group messaging in TextSecure v2.

[0] https://keybase.io/blog/introducing-keybase-teams#anyway-tea...

[maxtaco]

Thanks for the mention! We designed Keybase with these exact attacks in mind.