CVE-2020-15563
An issue was discovered in Xen through 4.13.x, allowing x86 HVM guest OS users to cause a hypervisor crash.
Does this matter?
Lower severity and a low EPSS score (0.41%). Track it; it rarely justifies an emergency change on its own.
Description
An issue was discovered in Xen through 4.13.x, allowing x86 HVM guest OS users to cause a hypervisor crash. An inverted conditional in x86 HVM guests' dirty video RAM tracking code allows such guests to make Xen de-reference a pointer guaranteed to point at unmapped space. A malicious or buggy HVM guest may cause the hypervisor to crash, resulting in Denial of Service (DoS) affecting the entire host. Xen versions from 4.8 onwards are affected. Xen versions 4.7 and earlier are not affected. Only x86 systems are affected. Arm systems are not affected. Only x86 HVM guests using shadow paging can leverage the vulnerability. In addition, there needs to be an entity actively monitoring a guest's video frame buffer (typically for display purposes) in order for such a guest to be able to leverage the vulnerability. x86 PV guests, as well as x86 HVM guests using hardware assisted paging (HAP), cannot leverage the vulnerability.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
- EPSS
- 0.41% probability · 35th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-119
- Affected
- xen/xen · debian/debian linux · fedoraproject/fedora · opensuse/leap
- Source
- cve@mitre.org
References
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00024.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00031.htmlMailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2020/07/07/3Mailing List, Third Party Advisory
- http://xenbits.xen.org/xsa/advisory-319.htmlPatch, Vendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXESCOVI7AVRNC7HEAMFM7PMEO6D3AUH/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VB3QJJZV23Z2IDYEMIHELWYSQBUEW6JP/
- https://security.gentoo.org/glsa/202007-02Third Party Advisory
- https://www.debian.org/security/2020/dsa-4723Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00024.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00031.htmlMailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2020/07/07/3Mailing List, Third Party Advisory
- http://xenbits.xen.org/xsa/advisory-319.htmlPatch, Vendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXESCOVI7AVRNC7HEAMFM7PMEO6D3AUH/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VB3QJJZV23Z2IDYEMIHELWYSQBUEW6JP/
- https://security.gentoo.org/glsa/202007-02Third Party Advisory
- https://www.debian.org/security/2020/dsa-4723Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.