An infinite-loop flaw was discovered in the QEMU emulator built with i8255x (PRO100) emulation support. When processing a chain of commands located in the Command Block List(CBL), each Command Block(CB) points to the next command in the list. If the link to the next CB pointed to the same block or if there was a closed loop in the chain, an infinite loop would execute the same command over and over again. A privileged user inside the guest could use this flaw to crash the QEMU instance, resulting in denial of service. http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-8345