CVE-2020-27675

Severity Score

4.7

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Se detectó un problema en el kernel de Linux versiones hasta 5.9.1, como es usado con Xen versiones hasta 4.14.x. El archivo drivers/xen/events/events_base.c permite la eliminación del canal de eventos durante el ciclo de manejo de eventos (una condición de carrera). Esto puede causar una desreferencia del puntero NULL y un uso de la memoria previamente liberada como es demostrado por un bloqueo dom0 por medio de eventos para un dispositivo paravirtualizado en reconfiguración, también se conoce como CID-073d0552ead5

*Credits: N/A

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Local

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

None

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-10-22 CVE Reserved
2020-10-22 CVE Published
2023-03-08 EPSS Updated
2024-08-04 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CWE-416: Use After Free
CWE-476: NULL Pointer Dereference

CAPEC

References (10)

URL	Tag	Source
http://www.openwall.com/lists/oss-security/2021/01/19/3	Mailing List
https://lists.debian.org/debian-lts-announce/2020/12/msg00015.html	Mailing List
https://lists.debian.org/debian-lts-announce/2020/12/msg00027.html	Mailing List

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=073d0552ead5bfc7a3a9c01de590e924f11b5dd2	2023-11-07
https://github.com/torvalds/linux/commit/073d0552ead5bfc7a3a9c01de590e924f11b5dd2	2023-11-07
https://xenbits.xen.org/xsa/advisory-331.html	2023-11-07

URL	Date	SRC
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3ZG6TZLD23QO3PV2AN2HB625ZX47ALTT	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6USZ4APZSBQDHGJLJMHW5JBN4QZV6SKZ	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GNF2R7FUT4IOJ2RIRGQ7X5R4F4FVVLSR	2023-11-07
https://security.gentoo.org/glsa/202011-06	2023-11-07

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				<= 5.9.1 Search vendor "Linux" for product "Linux Kernel" and version " <= 5.9.1"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				31 Search vendor "Fedoraproject" for product "Fedora" and version "31"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				32 Search vendor "Fedoraproject" for product "Fedora" and version "32"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				33 Search vendor "Fedoraproject" for product "Fedora" and version "33"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected