Allocation of Resources Without Limits or Throttling in Xen - CVE-2020-29486

Vulnerability details

The vulnerability allows a local privileged user to a crash the entire system.

An issue was discovered in Xen through 4.14.x. Nodes in xenstore have an ownership. In oxenstored, a owner could give a node away. However, node ownership has quota implications. Any guest can run another guest out of quota, or create an unbounded number of nodes owned by dom0, thus running xenstored out of memory A malicious guest administrator can cause a denial of service against a specific guest or against the whole host. All systems using oxenstored are vulnerable. Building and using oxenstored is the default in the upstream Xen distribution, if the Ocaml compiler is available. Systems using C xenstored are not vulnerable.

Affected software

How to mitigate CVE-2020-29486

External References

• https://www.debian.org/security/2020/dsa-4812
• https://xenbits.xenproject.org/xsa/advisory-352.html

Related Security Bulletins

• Allocation of Resources Without Limits or Throttling in Xen
• Allocation of Resources Without Limits or Throttling in xen (Alpine package)
• Debian update for xen
• Fedora 33 update for xen
• Fedora 32 update for xen