A NULL pointer dereference in TIFFClose() is caused by a failure to open an output file (non-existent path or a path that requires permissions like /dev/null) while specifying zones.

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Xen Management Tool DoS (XSA-323)

According to its self-reported version number, the Xen hypervisor installed on the remote host is affected by a denial of service vulnerability due to a bad path name limit in oxenstored. A malicious guest administrator can exploit this, by creating paths in the guest's own namespace that are too...