After several months of quietude, WordFence today started sending me this message:

• File appears to be malicious: …/zp-core/zp-extensions/viewer_size_image.php

I immediately downloaded the latest version of ZenPhoto and compared that file with the one on the server. They are identical.

Next steps?

-- Paul

I've reported what appears to be a false positive to the WordFence support team.

Thanks, reporting is best. If they insist, we need to know why actually. Although it is quite usual also for server side security measures to be a bit too tight at times.