Several vulnerabilities were discovered in qemu, a fast processor emulator. CVE-2015-3209 Matt Tait of Google"s Project Zero security team discovered a flaw in the way QEMU"s AMD PCnet Ethernet emulation handles multi-TMD packets with a length above 4096 bytes. A privileged guest user in a guest with an AMD PCNet ethernet card enabled can potentially use this flaw to execute arbitrary code on the host with the privileges of the hosting QEMU process. CVE-2015-4037 Kurt Seifried of Red Hat Product Security discovered that QEMU"s user mode networking stack uses predictable temporary file names when the -smb option is used. An unprivileged user can use this flaw to cause a denial of service. CVE-2015-4103 Jan Beulich of SUSE discovered that the QEMU Xen code does not properly restrict write access to the host MSI message data field, allowing a malicious guest to cause a denial of service. CVE-2015-4104 Jan Beulich of SUSE discovered that the QEMU Xen code does not properly restrict access to PCI MSI mask bits, allowing a malicious guest to cause a denial of service. CVE-2015-4105 Jan Beulich of SUSE reported that the QEMU Xen code enables logging for PCI MSI-X pass-through error messages, allowing a malicious guest to cause a denial of service. CVE-2015-4106 Jan Beulich of SUSE discovered that the QEMU Xen code does not properly restrict write access to the PCI config space for certain PCI pass-through devices, allowing a malicious guest to cause a denial of service, obtain sensitive information or potentially execute arbitrary code.