Steal Combat Maneuver vs a hidden object.

[artofcheatery]

Object was a magic gem whose location was discovered by a detect magic spell (overwhelming aura). The gem was hidden with a Sleight of Hand check which would require a DC 30 Perception to search for it. While I never decided where it was, I stated that it was somewhere on my torso and probably more than a move action for my character to take it out.

Could it be stolen via Combat Maneuver? If so, what would be the modifiers?

[Starglim]

Detect magic bypassed your Sleight of Hand check, for the same reason that blindsense would bypass your Stealth. It sounds as if its location is most similar to a sheathed weapon, so the DC for a Steal is your CMD + 5.

[artofcheatery]

So the only penalty for reaching into under my shirt and possibly my armor (while I am facing the other direction, because we did just start using facing) is a +5?

[Talonhawke]

And an AoO if they don't have the feat to make it go away.

[GM Hands of Fate]

So, i this case and in the case of stealing a sheathed weapon, if the opponent is flat-footed, do they get their Strength bonus to their CMD?