The file of
PDFBOX-2048 has a wrong encoded font length, it is 4412 in the PDF but it is really about 27350. This wrong length is used to read the encoded font stream and this results in further trouble (EOF).
The problem is that the wrong length is passed to createFilteredStream() instead of just calling it without parameters. In cosStream.doDecode() unFilteredStream = filteredStream (there is a FIXME there!!!), and in doDecode(COSName filterName, int filterIndex) unFilteredStream.getLength() is used, which returns the expectedLength.