CVE-2021-28039 Denial of service in n/a
A local user in a Xen PV guest can crash the Dom0 or driver domain via excessive I/O activity in specific kernel configurations.
- 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-2021-28039?
CVE-2021-28039 is a medium-severity denial of service vulnerability in Linux kernel, published on 5 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An issue was discovered in the Linux kernel 5.9.x through 5.11.3, as used with Xen. In some less-common configurations, an x86 PV guest OS user can crash a Dom0 or driver domain via a large amount of I/O activity. The issue relates to misuse of guest physical addresses when a configuration has CONFIG_XEN_UNPOPULATED_ALLOC but not CONFIG_XEN_BALLOON_MEMORY_HOTPLUG.
Weakness: CWE-131
Which versions are affected by CVE-2021-28039?
It affects 4 products.
Products include Linux kernel, Netapp Cloud Backup, Netapp Solidfire Baseboard Management Controller Firmware, Xen Xen.
How do I fix CVE-2021-28039?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-28039 being exploited?
There is no known exploitation of CVE-2021-28039 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-28039, GHSA-54vm-9r8q-f6f9, UBUNTU-CVE-2021-28039.