Vulnerability Description
An issue was discovered in Xen through 4.14.x. There is a race condition when migrating timers between x86 HVM vCPUs. When migrating timers of x86 HVM guests between its vCPUs, the locking model used allows for a second vCPU of the same guest (also operating on the timers) to release a lock that it didn't acquire. The most likely effect of the issue is a hang or crash of the hypervisor, i.e., a Denial of Service (DoS). All versions of Xen are affected. Only x86 systems are vulnerable. Arm systems are not vulnerable. Only x86 HVM guests can leverage the vulnerability. x86 PV and PVH cannot leverage the vulnerability. Only guests with more than one vCPU can exploit the vulnerability.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Xen | Xen | <= 4.14.0 |
| Fedoraproject | Fedora | 31 |
| Debian | Debian Linux | 10.0 |
| Opensuse | Leap | 15.2 |
Related Weaknesses (CWE)
References
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00008.htmlThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202011-06Third Party Advisory
- https://www.debian.org/security/2020/dsa-4769Third Party Advisory
- https://xenbits.xen.org/xsa/advisory-336.htmlPatchVendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00008.htmlThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202011-06Third Party Advisory
- https://www.debian.org/security/2020/dsa-4769Third Party Advisory
- https://xenbits.xen.org/xsa/advisory-336.htmlPatchVendor Advisory
FAQ
What is CVE-2020-25604?
CVE-2020-25604 is a vulnerability with a CVSS score of 4.7 (MEDIUM). An issue was discovered in Xen through 4.14.x. There is a race condition when migrating timers between x86 HVM vCPUs. When migrating timers of x86 HVM guests between its vCPUs, the locking model used ...
How severe is CVE-2020-25604?
CVE-2020-25604 has been rated MEDIUM with a CVSS base score of 4.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2020-25604?
Check the references section above for vendor advisories and patch information. Affected products include: Xen Xen, Fedoraproject Fedora, Debian Debian Linux, Opensuse Leap.