What is CVE-2024-49854?

CVE-2024-49854 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, classified as a Use After Free flaw (CWE-416), affecting Linux kernel versions from 4.19.323 onward and patched in 4.20, 5.5 and 5.11. CVE-2024-49854 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2024-49854?

CVE-2024-49854 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2024-49854?

Yes, CVE-2024-49854 has been patched. Fixed versions include 4.20, 5.5 and 5.11. If you are running Linux kernel 4.19.323 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2024-49854 actively exploited?

CVE-2024-49854 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-2024-49854

High

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for accessing waker_bfqq after splitting After commit 42c306ed7233 ("block, bfq: don't break merge chain in bfq_split_bfqq()"), if the current procress is the last holder of bfqq, the bfqq can be freed after bfq_split_bfqq(). Hence recored the bfqq and then access bfqq->waker_bfqq may trigger UAF. What's more, the waker_bfqq may in the merge chain of bfqq, hence just recored waker_bfqq is still not safe. Fix the problem by adding a helper bfq_waker_bfqq() to check if bfqq->waker_bfqq is in the merge chain, and current procress is the only holder.

Package Linux Kernel

Published 2024-10-21

Last modified 2025-11-03

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Weakness type

CWE-416

CVE-2024-49854 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 4.19.323, 5.4.285, 5.10.227 and later are affected. Fixed in 4.20, 5.5, 5.11 and their respective stable series.

Affected from

≥ 4.19.323 ≥ 5.4.285 ≥ 5.10.227

Fixed in

✓ 4.20 4.20.x ✓ 5.5 5.5.x ✓ 5.11 5.11.x

References

7 total

Kernel Git
https://git.kernel.org/stable/c/0780451f03bf518bc032a7c584de8f92e2d39d7f

Patch
Kernel Git
https://git.kernel.org/stable/c/0b8bda0ff17156cd3f60944527c9d8c9f99f1583

Patch
Kernel Git
https://git.kernel.org/stable/c/1ba0403ac6447f2d63914fb760c44a3b19c44eaf

Patch
Kernel Git
https://git.kernel.org/stable/c/63a07379fdb6c72450cb05294461c6016b8b7726

Patch
Kernel Git
https://git.kernel.org/stable/c/cae58d19121a70329cf971359e2518c93fec04fe

Patch

Showing 5 of 7 references View all on NVD

Details

CVE ID CVE-2024-49854

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2024-10-21

Modified 2025-11-03

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2024-49854?

CVE-2024-49854 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 4.19.323 onward and has been patched in 4.20, 5.5 and 5.11. CVE-2024-49854 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2024-49854?

CVE-2024-49854 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2024-49854?

Yes. CVE-2024-49854 has been patched. Fixed versions include 4.20, 5.5 and 5.11. If you are running Linux kernel 4.19.323 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2024-49854 actively exploited?

No. CVE-2024-49854 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.