What is CVE-2021-47456?

CVE-2021-47456 is a High severity Linux kernel vulnerability with a CVSS score of 8.4 out of 10, classified as a Use After Free flaw (CWE-416), affecting Linux kernel versions from 3.4 onward and patched in 4.4.290, 4.9.288, 4.14.253 and others. CVE-2021-47456 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47456?

CVE-2021-47456 has a CVSS score of 8.4 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2021-47456?

Yes, CVE-2021-47456 has been patched. Fixed versions include 4.4.290, 4.9.288, 4.14.253 and others. If you are running Linux kernel 3.4 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47456 actively exploited?

CVE-2021-47456 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Use After Free (CWE-416)?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/416.html

CVE-2021-47456

High

In the Linux kernel, the following vulnerability has been resolved: can: peak_pci: peak_pci_remove(): fix UAF When remove the module peek_pci, referencing 'chan' again after releasing 'dev' will cause UAF. Fix this by releasing 'dev' later. The following log reveals it: [ 35.961814 ] BUG: KASAN: use-after-free in peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.963414 ] Read of size 8 at addr ffff888136998ee8 by task modprobe/5537 [ 35.965513 ] Call Trace: [ 35.965718 ] dump_stack_lvl+0xa8/0xd1 [ 35.966028 ] print_address_description+0x87/0x3b0 [ 35.966420 ] kasan_report+0x172/0x1c0 [ 35.966725 ] ? peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.967137 ] ? trace_irq_enable_rcuidle+0x10/0x170 [ 35.967529 ] ? peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.967945 ] __asan_report_load8_noabort+0x14/0x20 [ 35.968346 ] peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.968752 ] pci_device_remove+0xa9/0x250

Package Linux Kernel

Published 2024-05-22

Last modified 2025-04-02

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

8.4

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness type

CWE-416

CVE-2021-47456 is a Use After Free vulnerability

What is Use After Free?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE

Affected versions

Linux kernel versions 3.4 and later are affected. Fixed in 4.4.290, 4.9.288, 4.14.253, 4.19.214, 5.4.156, 5.10.76, 5.14.15, 5.15 and their respective stable series.

Affected from

≥ 3.4

Fixed in

✓ 4.4.290 4.4.x ✓ 4.9.288 4.9.x ✓ 4.14.253 4.14.x ✓ 4.19.214 4.19.x ✓ 5.4.156 5.4.x ✓ 5.10.76 5.10.x ✓ 5.14.15 5.14.x ✓ 5.15

References

8 total

Kernel Git
https://git.kernel.org/stable/c/0e5afdc2315b0737edcf55bede4ee1640d2d464d

Patch
Kernel Git
https://git.kernel.org/stable/c/1248582e47a9f7ce0ecd156c39fc61f8b6aa3699

Patch
Kernel Git
https://git.kernel.org/stable/c/1c616528ba4aeb1125a06b407572ab7b56acae38

Patch
Kernel Git
https://git.kernel.org/stable/c/28f28e4bc3a5e0051faa963f10b778ab38c1db69

Patch
Kernel Git
https://git.kernel.org/stable/c/34914971bb3244db4ce2be44e9438a9b30c56250

Patch

Showing 5 of 8 references View all on NVD

Details

CVE ID CVE-2021-47456

Severity High

CVSS score 8.4 / 10

CVSS version 3.1

Published 2024-05-22

Modified 2025-04-02

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47456?

CVE-2021-47456 is a High severity Linux kernel vulnerability with a CVSS score of 8.4 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 3.4 onward and has been patched in 4.4.290, 4.9.288, 4.14.253 and others. CVE-2021-47456 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47456?

CVE-2021-47456 has a CVSS score of 8.4 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2021-47456?

Yes. CVE-2021-47456 has been patched. Fixed versions include 4.4.290, 4.9.288, 4.14.253 and others. If you are running Linux kernel 3.4 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47456 actively exploited?

No. CVE-2021-47456 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.