CVE-2021-28709 Other in xen
Insufficient error handling in Xen hypervisor PoD mode allows guest-triggered denial of service via partial P2M update failures.
- 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-2021-28709?
CVE-2021-28709 is a high-severity vulnerability in Debian Debian Linux, published on 24 Nov 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
issues with partially successful P2M updates on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assigned. Guests are permitted to control certain P2M aspects of individual pages via hypercalls. These hypercalls may act on ranges of pages specified via page orders (resulting in a power-of-2 number of pages). In some cases the hypervisor carries out the requests by splitting them into smaller chunks. Error handling in certain PoD cases has been insufficient in that in particular partial success of some operations was not properly accounted for. There are two code paths affected - page removal (CVE-2021-28705) and insertion of new pages (CVE-2021-28709). (We provide one patch which combines the fix to both issues.)
Weakness: CWE-755
Which versions are affected by CVE-2021-28709?
It affects 3 products.
Products include Debian Debian Linux, Fedoraproject Fedora, Xen Xen.
How do I fix CVE-2021-28709?
Apply the vendor's patch.
Is CVE-2021-28709 being exploited?
There is no known exploitation of CVE-2021-28709 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as ALPINE-CVE-2021-28709, DEBIAN-CVE-2021-28709, GHSA-5rjh-29pm-3mx4, UBUNTU-CVE-2021-28709.