CVE-2016-7909: The pcnet_rdra_addr function in hw/net/pcnet.c in QEMU (aka Quick Emulator) allows local guest OS administr...

Security readout for executives and security teams

This is a denial-of-service flaw in QEMU's emulated PCnet network device. A privileged administrator inside a guest VM could set a descriptor ring length to zero, causing an infinite loop and crashing the QEMU process. The main business impact is VM outage, not data theft or remote takeover based on the supplied evidence. Exposure is most relevant on virtualization hosts running QEMU VMs configured with the PCnet emulated network device, especially where guest administrators are not fully trusted. The bundle does not identify specific affected QEMU versions or distributions beyond vendor update references. Treat this as a targeted availability issue for QEMU virtualization environments. It is not supported as remotely exploitable in the supplied sources, but it matters where guest administrators are separate from infrastructure owners or where VM uptime is business-critical. Mitigation focus: Apply QEMU security updates from the relevant vendor or Linux distribution.; Confirm the installed QEMU includes the pcnet rx/tx descriptor ring length checks.; Review vendor advisories from Gentoo, openSUSE, Debian, or your platform supplier..

Prepared

Jun 13, 2026, 13:39 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.