CVE-2019-20934

kernel: use-after-free in show_numa_stats function

Severity Score

5.3

*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 before 5.2.6. On NUMA systems, the Linux fair scheduler has a use-after-free in show_numa_stats() because NUMA fault statistics are inappropriately freed, aka CID-16d51a590a8c.

Se detectó un problema en el kernel de Linux versiones anteriores a 5.2.6. En los sistemas NUMA, el programador fair de Linux presenta un uso de la memoria previamente liberada en la función show_numa_stats() porque las estadísticas de fallo de NUMA son liberadas inapropiadamente, también se conoce como CID-16d51a590a8c

A flaw was found in the Linux kernel’s implementation of displaying NUMA statistics, where displaying the scheduler statistics could trigger a use-after-free in show_numa_stats() and display the kernel memory to userspace. The highest threat from this vulnerability is to system availability.

*Credits: N/A

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Attack Vector

Local

Attack Complexity

Medium

Authentication

None

Confidentiality

Partial

Integrity

None

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-11-28 CVE Reserved
2020-11-28 CVE Published
2023-03-08 EPSS Updated
2024-08-05 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-416: Use After Free

CAPEC

References (5)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=16d51a590a8ce3befb1308e0e7ab77f3b661af33	2021-01-12

URL	Date	SRC
https://bugs.chromium.org/p/project-zero/issues/detail?id=1913	2021-01-12
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.2.6	2021-01-12
https://access.redhat.com/security/cve/CVE-2019-20934	2021-10-26
https://bugzilla.redhat.com/show_bug.cgi?id=1902788	2021-10-26

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"				>= 4.19 < 4.19.64 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.19 < 4.19.64"		-		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 5.2 <= 5.2.17 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.2 <= 5.2.17"		-		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				5.3 Search vendor "Linux" for product "Linux Kernel" and version "5.3"		rc1		Affected