1. Complex implementation: lots of moving parts with a lot of room for defects
2. Complex configuration: lots of configuration settings with a lot of room for misconfiguration
3. Complex protocols: overcomplicated handshaking and key negotiation
All these things leave a lot of flexibility for backdooring, binary exploitation, etc. aka "capabilities" in spook-speak.
1. Complex implementation: lots of moving parts with a lot of room for defects
2. Complex configuration: lots of configuration settings with a lot of room for misconfiguration
3. Complex protocols: overcomplicated handshaking and key negotiation
All these things leave a lot of flexibility for backdooring, binary exploitation, etc. aka "capabilities" in spook-speak.