CVE-2023-34322 top-level shadow reference dropped too early for 64-bit PV guests
A race condition in Xen's shadow paging for 64-bit PV guests allows attackers to escalate privileges or cause denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-34322?
CVE-2023-34322 is a high-severity vulnerability in Xen Xen, published on 5 Jan 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. Since Xen itself needs to be mapped when PV guests run, Xen and shadowed PV guests run directly the respective shadow page tables. For 64-bit PV guests this means running on the shadow of the guest root page table.
In the course of dealing with shortage of memory in the shadow pool associated with a domain, shadows of page tables may be torn down. This tearing down may include the shadow root page table that the CPU in question is presently running on. While a precaution exists to supposedly prevent the tearing down of the underlying live page table, the time window covered by that precaution isn't large enough.
Weakness: CWE-273
Which versions are affected by CVE-2023-34322?
It affects 1 product.
Products include Xen Xen.
How do I fix CVE-2023-34322?
Apply the vendor's patch.
Is CVE-2023-34322 being exploited?
There is no known exploitation of CVE-2023-34322 in the wild and no public exploit code.
Other vulnerabilities in Xen Xen
Sources
Also known as ALPINE-CVE-2023-34322, DEBIAN-CVE-2023-34322, GHSA-3qxp-p56x-r4h3, UBUNTU-CVE-2023-34322.