If using a foreign iMac as an external display (through the Thunderbolt to Thunderbolt, or Mini DisplayPort to Mini DisplayPort cable, and Command+F2 on the iMac, as per iMac Target Display Mode FAQ), is there a chance that my MacBook or ThinkPad could get infected with some sort viruses through the said port, have the keystrokes recorded, or get its screen captured by the aforementioned iMac?
I'm specifically interested in the aspect of making sure that my laptop is not subject to these attacks, but I guess Thunderbolt is a double-way street.
I see that according to Wikipedia, it appears that Thunderbolt may be subject to DMA attacks, but only in certain circumstances. If my ThinkPad X230 has a "++DP" logo next to its port, does it mean it's not vulnerable? How do you determine if you may or may not be vulnerable? Is there a way to minimise any possible privilege escalation?