Brake fluid leak? With pics

[jme144]

Can anyone have a look at these pics and tell me if it's a brake fluid leak? I've had the stop and handbrake lights flash and stay on in the past week or so and now I've just noticed this moisture on the rear right tyre, all other tyre side walls being dry
Any help would be great

 

[dangerous dave]

Has your level dropped? Clean it all off as it'll eat the paint..

When you done, you'll need to try and force the leak to show itself, might be a hose or the piston.