IssueTracker

Library used exifinterface
Version used: 25.1.0
Theme used: n/a
Devices/Android versions reproduced on: all

The new ExifInterface implementation determines the file type of a file before it reads / writes changes. This is the relevant code:

    private int getMimeType(BufferedInputStream in) throws IOException {
        in.mark(SIGNATURE_CHECK_SIZE);
        byte[] signatureCheckBytes = new byte[SIGNATURE_CHECK_SIZE];
        if (in.read(signatureCheckBytes) != SIGNATURE_CHECK_SIZE) {
            throw new EOFException();
        }
        ...
    }

Note here how the exact number of read bytes are checked - SIGNATURE_CHECK_SIZE is set to 5000. Now, if I have a smaller JPEG file - for example 100x200 monotone colored (guess what, I created that for a Unit test!) - this file will not be accepted neither for reading nor writing EXIF information.

On the contrary, the old platform implementation has no such restriction, but is of course considered unsafe.