I just got the same thing. Trying to use DDX to add a PageContent element to a PDF.
It doesn't happen on all documents, so I think it must be something wrong with the source PDF?
Actually, it had nothing to do with a SVG named color. It had to do with the fact that my DDX statement
<DDX source='doc_source' pages='2-last' />
expects 2 pages and it was only supplied a 1 page document.
I had to add a couple steps at the beginning of my processing to fetch how many pages the PDF had and then determine whether to add the additional pages.