CVE-2024-49854

HIGH EPSS 12.0%
Published Oct 21, 20241y ago · Modified Jun 17, 20261w ago
7.8 CVSS 3.1
High
Find Similar
Published Oct 21, 2024 1y ago
Last Modified Jun 17, 2026 1w ago

Description

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.

CVSS Details

Base Score
7.8
Exploitability
1.8
Impact
5.9
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
12.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-416 Use After Free Memory Safety

Affected Products 5

VendorProductVersionRange
linuxlinux_kernel*≥5.10.227  –  <5.15.168
linuxlinux_kernel*≥5.16  –  <6.1.113
linuxlinux_kernel*≥6.2  –  <6.6.54
linuxlinux_kernel*≥6.7  –  <6.10.13
linuxlinux_kernel*≥6.11  –  <6.11.2

References 7

  • git.kernel.org https://git.kernel.org/stable/c/0780451f03bf518bc032a7c584de8f92e2d39d7f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/0b8bda0ff17156cd3f60944527c9d8c9f99f1583
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/1ba0403ac6447f2d63914fb760c44a3b19c44eaf
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/63a07379fdb6c72450cb05294461c6016b8b7726
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/cae58d19121a70329cf971359e2518c93fec04fe
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/de0456460f2abf921e356ed2bd8da87a376680bd
    Patch
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/0780451f03bf518bc032a7c584de8f92e2d39d7f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/0b8bda0ff17156cd3f60944527c9d8c9f99f1583
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/1ba0403ac6447f2d63914fb760c44a3b19c44eaf
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/63a07379fdb6c72450cb05294461c6016b8b7726
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/cae58d19121a70329cf971359e2518c93fec04fe
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/de0456460f2abf921e356ed2bd8da87a376680bd
    Patch