CVE-2020-15565

MITRE NVD CVE.ORG Print: PDF PDF

Summary

CVECVE-2020-15565
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2020-07-07 13:15:00 UTC
Updated2023-11-07 03:17:00 UTC
DescriptionAn issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS users to cause a host OS denial of service or possibly gain privileges because of insufficient cache write-back under VT-d. When page tables are shared between IOMMU and CPU, changes to them require flushing of both TLBs. Furthermore, IOMMUs may be non-coherent, and hence prior to flushing IOMMU TLBs, a CPU cache also needs writing back to memory after changes were made. Such writing back of cached data was missing in particular when splitting large page mappings into smaller granularity ones. A malicious guest may be able to retain read/write DMA access to frames returned to Xen's free pool, and later reused for another purpose. Host crashes (leading to a Denial of Service) and privilege escalation cannot be ruled out. Xen versions from at least 3.2 onwards are affected. Only x86 Intel systems are affected. x86 AMD as well as Arm systems are not affected. Only x86 HVM guests using hardware assisted paging (HAP), having a passed through PCI device assigned, and having page table sharing enabled can leverage the vulnerability. Note that page table sharing will be enabled (by default) only if Xen considers IOMMU and CPU large page size support compatible.

Risk And Classification

Problem Types: CWE-400

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Debian Debian Linux 10.0 All All All
Operating System Debian Debian Linux 10.0 All All All
Operating System Fedoraproject Fedora 31 All All All
Operating System Fedoraproject Fedora 32 All All All
Operating System Opensuse Leap 15.1 All All All
Operating System Opensuse Leap 15.2 All All All
Operating System Xen Xen All All All All

References

ReferenceSourceLinkTags
Xen: Multiple vulnerabilities (GLSA 202007-02) — Gentoo security GENTOO security.gentoo.org
[SECURITY] Fedora 31 Update: xen-4.12.3-3.fc31 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 32 Update: xen-4.13.1-4.fc32 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[security-announce] openSUSE-SU-2020:0985-1: important: Security update SUSE lists.opensuse.org
oss-security - Xen Security Advisory 321 v3 (CVE-2020-15565) - insufficient cache write-back under VT-d MLIST www.openwall.com Mailing List, Third Party Advisory
[SECURITY] Fedora 32 Update: xen-4.13.1-4.fc32 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[SECURITY] Fedora 31 Update: xen-4.12.3-3.fc31 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[security-announce] openSUSE-SU-2020:0965-1: important: Security update SUSE lists.opensuse.org
Debian -- Security Information -- DSA-4723-1 xen DEBIAN www.debian.org Third Party Advisory
XSA-321 - Xen Security Advisories MISC xenbits.xen.org Patch, Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 198943 Ubuntu Security Notification for Xen Vulnerabilities (USN-5617-1)
  • 378880 Citrix XenServer Security Updates (CTX277456)
  • 500790 Alpine Linux Security Update for xen
  • 501510 Alpine Linux Security Update for xen
  • 504534 Alpine Linux Security Update for xen
© CVE.report 2026 |

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

CVE.report and Source URL Uptime Status status.cve.report