CVE-2020-25596

CVSS V2 Low 2.1 CVSS V3 Medium 5.5
Description
An issue was discovered in Xen through 4.14.x. x86 PV guest kernels can experience denial of service via SYSENTER. The SYSENTER instruction leaves various state sanitization activities to software. One of Xen's sanitization paths injects a #GP fault, and incorrectly delivers it twice to the guest. This causes the guest kernel to observe a kernel-privilege #GP fault (typically fatal) rather than a user-privilege #GP fault (usually converted into SIGSEGV/etc.). Malicious or buggy userspace can crash the guest kernel, resulting in a VM Denial of Service. All versions of Xen from 3.2 onwards are vulnerable. Only x86 systems are vulnerable. ARM platforms are not vulnerable. Only x86 systems that support the SYSENTER instruction in 64bit mode are vulnerable. This is believed to be Intel, Centaur, and Shanghai CPUs. AMD and Hygon CPUs are not believed to be vulnerable. Only x86 PV guests can exploit the vulnerability. x86 PVH / HVM guests cannot exploit the vulnerability.
Overview
  • CVE ID
  • CVE-2020-25596
  • Assigner
  • cve@mitre.org
  • Vulnerability Status
  • Analyzed
  • Published Version
  • 2020-09-23T22:15:13
  • Last Modified Date
  • 2022-11-21T14:24:57
CPE Configuration (Product)
CPE Vulnerable Operator Version Start Version End
cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:* 1 OR 3.2.0 4.14.0
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* 1 OR
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* 1 OR
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* 1 OR
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* 1 OR
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:* 1 OR
CVSS Version 2
  • Version
  • 2.0
  • Vector String
  • AV:L/AC:L/Au:N/C:N/I:N/A:P
  • Access Vector
  • LOCAL
  • Access Compatibility
  • LOW
  • Authentication
  • NONE
  • Confidentiality Impact
  • NONE
  • Integrity Impact
  • NONE
  • Availability Impact
  • PARTIAL
  • Base Score
  • 2.1
  • Severity
  • LOW
  • Exploitability Score
  • 3.9
  • Impact Score
  • 2.9
CVSS Version 3
  • Version
  • 3.1
  • Vector String
  • CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
  • Attack Vector
  • LOCAL
  • Attack Compatibility
  • LOW
  • Privileges Required
  • LOW
  • User Interaction
  • NONE
  • Scope
  • UNCHANGED
  • Confidentiality Impact
  • NONE
  • Availability Impact
  • HIGH
  • Base Score
  • 5.5
  • Base Severity
  • MEDIUM
  • Exploitability Score
  • 1.8
  • Impact Score
  • 3.6
History
Created Old Value New Value Data Type Notes
2022-05-10 16:20:13 Added to TrackCVE
2022-12-04 23:13:35 2020-09-23T22:15Z 2020-09-23T22:15:13 CVE Published Date updated
2022-12-04 23:13:35 2022-11-21T14:24:57 CVE Modified Date updated
2022-12-04 23:13:35 Analyzed Vulnerability Status updated