Seekable did not record whether it was initialized. On a fresh Seekable, or one whose init buff() failed, decompress, offset to frame index and frame decompressed size made the C library read a NULL seek table. After a failed re-initialization, decompress returned data from the refused buffer using the previous seek table.

Separately, frame decompressed size(num frames()), on Seekable and SeekTable, read one entry past the end of the seek table.

The flaw was corrected by refusing to use a Seekable until an initialization succeeded, and by checking the frame index.