CVE-2020-25603

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Summary

CVECVE-2020-25603
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2020-09-23 22:15:00 UTC
Updated2023-11-07 03:20:00 UTC
DescriptionAn issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier (e.g., smp_*mb()) to prevent both the compiler and CPU from re-ordering access. A malicious guest may be able to cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded. Systems running all versions of Xen are affected. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all systems, the presence and the scope of the vulnerability depend on the precise re-ordering performed by the compiler used to build Xen. We have not been able to survey compilers; consequently we cannot say which compiler(s) might produce vulnerable code (with which code generation options). GCC documentation clearly suggests that re-ordering is possible. Arm systems will also be vulnerable if the CPU is able to re-order memory access. Please consult your CPU vendor. x86 systems are only vulnerable if a compiler performs re-ordering.

Risk And Classification

Problem Types: CWE-670

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
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 Fedoraproject Fedora 33 All All All
Operating System Opensuse Leap 15.2 All All All
Operating System Xen Xen All All All All

References

ReferenceSourceLinkTags
[SECURITY] Fedora 32 Update: xen-4.13.1-6.fc32 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
Xen: Multiple vulnerabilities (GLSA 202011-06) — Gentoo security GENTOO security.gentoo.org
[SECURITY] Fedora 33 Update: xen-4.14.0-5.fc33 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
XSA-340 - Xen Security Advisories MISC xenbits.xen.org Patch, Vendor Advisory
[SECURITY] Fedora 31 Update: xen-4.12.3-5.fc31 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[SECURITY] Fedora 31 Update: xen-4.12.3-5.fc31 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 32 Update: xen-4.13.1-6.fc32 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org Third Party Advisory
[security-announce] openSUSE-SU-2020:1608-1: important: Security update SUSE lists.opensuse.org Third Party Advisory
Debian -- Security Information -- DSA-4769-1 xen DEBIAN www.debian.org Third Party Advisory
[SECURITY] Fedora 33 Update: xen-4.14.0-5.fc33 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org 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)
  • 500792 Alpine Linux Security Update for xen
  • 501512 Alpine Linux Security Update for xen
  • 504536 Alpine Linux Security Update for xen
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