An integer underflow leading to array index error was found in the way gzip used to decompress files / archives, compressed with the Lempel–Ziv–Welch (LZW) compression algorithm. A remote attacker could provide a specially-crafted LZW compressed gzip archive, which once decompressed by a local, unsuspecting user would lead to gzip crash, or, potentially to arbitrary code execution with the privileges of the user running gzip.

Upstream patch: --------------- http://git.savannah.gnu.org/cgit/gzip.git/commit/?id=a3db5806d012082b9e25cc36d09f19cd736a468f

Acknowledgements:

Red Hat would like to thank Aki Helin of the Oulu University Secure Programming Group for responsibly reporting this flaw.