Pillow, a Python imaging library, has a vulnerability in versions prior to 13.0.0 where its P;2L and P;4L raw decoders can read beyond the end of an input buffer. This flaw allows disclosure of up to three adjacent heap bytes or can cause a crash. The issue arises because the unpackers read padded bit planes separately, potentially exceeding the buffer size calculated by ImagingRawDecode. This vulnerability is fixed in version 13.0.0.