Do concerns about Sony A7 light leaks hold water?

"Light leak" from Sony A7, 30 sec, ISO 25,600, two bright flashlights shining on lens flange.

Canon 5D Mark III, 30 seconds, ISO 25,600, sunlight. Sigma 70mm f/2.8 Macro.

Nikon D800E, 30 seconds, ISO 25,600, sunlight. Sigma 70mm f/2.8 Macro.