A flaw was found in libvirt. A refactor of the code fetching the list of interfaces for multiple APIs introduced a corner case on platforms where allocating 0 bytes of memory results in a NULL pointer. This corner case would lead to a NULL-pointer dereference and subsequent crash of virtinterfaced. This issue could allow clients connecting to the read-only socket to crash the virtinterfaced daemon.

An off-by-one error flaw was found in the udevListInterfacesByStatus() function in libvirt when the number of interfaces exceeds the size of the `names` array. This issue can be reproduced by sending specially crafted data to the libvirt daemon, allowing an unprivileged client to perform a denial of service attack by causing the libvirt daemon to crash.

A race condition leading to a stack use-after-free flaw was found in libvirt. Due to a bad assumption in the virNetClientIOEventLoop() method, the `data` pointer to a stack-allocated virNetClientIOEventData structure ended up being used in the virNetClientIOEventFD callback while the data pointer's stack frame was concurrently being "freed" when returning from virNetClientIOEventLoop(). The 'virtproxyd' daemon can be used to trigger requests. If libvirt is configured with fine-grained access control, this issue, in theory, allows a user to escape their otherwise limited access. This flaw allows a local, unprivileged user to access virtproxyd without authenticating. Remote users would need to authenticate before they could access it.

A NULL pointer dereference flaw was found in the udevConnectListAllInterfaces() function in libvirt. This issue can occur when detaching a host interface while at the same time collecting the list of interfaces via virConnectListAllInterfaces API. This flaw could be used to perform a denial of service attack by causing the libvirt daemon to crash.