{"api_version":"1","generated_at":"2026-04-23T03:36:58+00:00","cve":"CVE-2020-11739","urls":{"html":"https://cve.report/CVE-2020-11739","api":"https://cve.report/api/cve/CVE-2020-11739.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2020-11739","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2020-11739"},"summary":{"title":"CVE-2020-11739","description":"An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the \"critical\" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. 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Information leak and privilege escalation cannot be excluded.","Type":"Description","Title":null},{"CveYear":"2020","CveId":"11739","Ordinal":"2","NoteData":"2020-04-14","Type":"Other","Title":"Published"},{"CveYear":"2020","CveId":"11739","Ordinal":"3","NoteData":"2020-07-13","Type":"Other","Title":"Modified"}]}}}