CVE-2020-27675medium
New! CVE Severity Now Using CVSS v3
The calculated severity for CVEs has been updated to use CVSS v3 by default. CVEs that do not have a CVSS v3 score will fall back CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.
Description
An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device, aka CID-073d0552ead5.
References
https://github.com/torvalds/linux/commit/073d0552ead5bfc7a3a9c01de590e924f11b5dd2
https://xenbits.xen.org/xsa/advisory-331.html
https://security.gentoo.org/glsa/202011-06
https://lists.debian.org/debian-lts-announce/2020/12/msg00015.html
https://lists.debian.org/debian-lts-announce/2020/12/msg00027.html
Details
Source: MITRE
Published: 2020-10-22
Updated: 2021-07-21
Type: CWE-362
Risk Information
CVSS v2
Base Score: 4.7
Vector: AV:L/AC:M/Au:N/C:N/I:N/A:C
Impact Score: 6.9
Exploitability Score: 3.4
Severity: MEDIUM
CVSS v3
Base Score: 4.7
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 1
Severity: MEDIUM
Vulnerable Software
Configuration 1
OR
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions up to 5.9.1 (inclusive)
Configuration 2
OR
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
Tenable Plugins
| ID | Name | Product | Family | Severity |
|---|---|---|---|---|
| 151307 | EulerOS Virtualization for ARM 64 3.0.2.0 : kernel (EulerOS-SA-2021-2075) | Nessus | Huawei Local Security Checks | high |
| 147978 | Ubuntu 20.04 LTS / 20.10 : Linux kernel vulnerabilities (USN-4751-1) | Nessus | Ubuntu Local Security Checks | high |
| 147690 | EulerOS Virtualization 2.9.0 : kernel (EulerOS-SA-2021-1642) | Nessus | Huawei Local Security Checks | high |
| 147512 | EulerOS Virtualization 2.9.1 : kernel (EulerOS-SA-2021-1604) | Nessus | Huawei Local Security Checks | high |
| 145005 | Amazon Linux AMI : kernel (ALAS-2021-1461) | Nessus | Amazon Linux Local Security Checks | medium |
| 144752 | Ubuntu 16.04 LTS : Linux kernel vulnerabilities (USN-4681-1) | Nessus | Ubuntu Local Security Checks | high |
| 144750 | Ubuntu 18.04 LTS / 20.04 LTS : Linux kernel vulnerabilities (USN-4679-1) | Nessus | Ubuntu Local Security Checks | medium |
| 144749 | Ubuntu 16.04 LTS / 18.04 LTS : Linux kernel vulnerabilities (USN-4680-1) | Nessus | Ubuntu Local Security Checks | medium |
| 144693 | EulerOS 2.0 SP9 : kernel (EulerOS-SA-2021-1028) | Nessus | Huawei Local Security Checks | high |
| 144687 | EulerOS 2.0 SP9 : kernel (EulerOS-SA-2021-1009) | Nessus | Huawei Local Security Checks | high |
| 144494 | Debian DLA-2494-1 : linux security update | Nessus | Debian Local Security Checks | high |
| 144464 | Amazon Linux AMI : kernel (ALAS-2020-1462) (deprecated) | Nessus | Amazon Linux Local Security Checks | high |
| 144168 | EulerOS 2.0 SP8 : kernel (EulerOS-SA-2020-2514) | Nessus | Huawei Local Security Checks | medium |
| 144097 | Debian DLA-2483-1 : linux-4.19 security update | Nessus | Debian Local Security Checks | high |
| 144068 | Photon OS 3.0: Linux PHSA-2020-3.0-0174 | Nessus | PhotonOS Local Security Checks | medium |
| 144062 | Photon OS 1.0: Linux PHSA-2020-1.0-0345 | Nessus | PhotonOS Local Security Checks | medium |
| 143875 | SUSE SLES15 Security Update : kernel (SUSE-SU-2020:3532-1) | Nessus | SuSE Local Security Checks | high |
| 143857 | SUSE SLES12 Security Update : kernel (SUSE-SU-2020:3544-1) | Nessus | SuSE Local Security Checks | high |
| 143809 | SUSE SLED15 / SLES15 Security Update : kernel (SUSE-SU-2020:3272-1) | Nessus | SuSE Local Security Checks | high |
| 143773 | SUSE SLES12 Security Update : kernel (SUSE-SU-2020:3281-1) | Nessus | SuSE Local Security Checks | high |
| 143589 | Amazon Linux 2 : kernel (ALAS-2020-1566) | Nessus | Amazon Linux Local Security Checks | medium |
| 142854 | GLSA-202011-06 : Xen: Multiple vulnerabilities | Nessus | Gentoo Local Security Checks | high |
| 142338 | Fedora 33 : kernel (2020-474d747b60) | Nessus | Fedora Local Security Checks | medium |
| 142291 | Fedora 31 : kernel (2020-09e4d062fe) | Nessus | Fedora Local Security Checks | medium |
| 142229 | Fedora 32 : kernel (2020-920a258c79) | Nessus | Fedora Local Security Checks | medium |