An issue was discovered in Xen through 4.14.x. Some OSes (such as Linux, FreeBSD, and NetBSD) are processing watch events using a single thread. If the events are received faster than the thread is able to handle, they will get queued. As the queue is unbounded, a guest may be able to trigger an OOM in the backend. All systems with a FreeBSD, Linux, or NetBSD (any version) dom0 are vulnerable.
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.
| Link | Tags |
|---|---|
| https://xenbits.xenproject.org/xsa/advisory-349.html | patch vendor advisory |
| https://www.debian.org/security/2021/dsa-4843 | third party advisory vendor advisory |
| https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html | third party advisory mailing list |
| https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html | third party advisory mailing list |
| https://security.gentoo.org/glsa/202107-30 | third party advisory vendor advisory |