Too many IDAT's found

[hexmode]

While looking at WikiApiary, I found this thumbnail failure: https://wikiapiary.com/wiki/File:IndianerWiki_Logo.png

That lead me to this bug: https://bugzilla.wikimedia.org/41374

A proposed solution there is "Just use GIMP (open, save) to create a 'proper' PNG".

Is there any way to get ImageMagick to handle these?

[snibgo]

I'm confused by all the links, and can't nail down a problem. For example, https://upload.wikimedia.org/wikipedia/ ... dither.png converts for me without a problem.

Can you provide a link to a single image that shows the problem?

[glennrp]

Extra IDAT could be a place to hide malware, although it could also be the case that the extra IDAT was simply created accidentally and contains random junk.

I don't see a problem with how IM-6.8.9-9 handles https://wikiapiary.com/w/images/wikiapi ... i_Logo.png though; there is a warning
about "Too many IDATs" but the file is converted properly. If you are using an old libpng version, the file might be rejected. From your warning
message (with an apostrophe in "IDAT's" that has been since removed), I think you are using libpng 1.2.x, which will reject the file.