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We found a bunch of data which is zip files with random data absent (and replaced with 0-bytes.)
As a result, InflaterHuffmanTree.buildTree(byte) receives empty byte arrays, and doesn't notice that the data is invalid. In this particular case I can see that codeLengths is a byte where all 11 bytes are zero. The result is that tree is a byte where all 512 bytes are zero.
I suspect that it's impossible for a Huffman tree to have any entries which are 0 (could someone confirm this though?) in which case any 0 entries would be invalid. But is there a better check which could be performed to ensure that the tree data is intact?
Sun's implementation throws an exception indicating that the Huffman tree is incomplete, which appears to be the correct error in this situation.
I will roll this into 36560 as it turns out it's related.
*** This bug has been marked as a duplicate of 36560 ***