CVE-2020-29487

CVE-2020-29487 describes a denial-of-service vulnerability in Xen XAPI versions prior to 2020-12-15. A malicious or buggy guest can exploit an O(N^2) time complexity issue in xenopsd's xenstore key watching logic and O(M*N) space complexity in message-switch, leading to excessive memory consumption in dom0. This can result in host denial of service through thrashing or out-of-memory errors. Rated with a CVSS score of 7.5 (HIGH), this vulnerability is remotely exploitable with low attack complexity and no user interaction required, impacting availability. There is currently no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.