Sign in Sign up
JA · EN · FR
SecPulse
Categories
CVE-2024-49867 high CVSS 7.8

Use-After-Free in Linux kernel (CVE-2024-49867)

Summary

Vulnerability in Linux kernel (CVE-2024-49867). Successful exploitation can lead to full system takeover.

Original description

The description as published by the source.

In the Linux kernel, the following vulnerability has been resolved:

btrfs: wait for fixup workers before stopping cleaner kthread during umount

During unmount, at close_ctree(), we have the following steps in this order:

  1. Park the cleaner kthread - this doesn't destroy the kthread, it basically
    halts its execution (wake ups against it work but do nothing);

  2. We stop the cleaner kthread - this results in freeing the respective
    struct task_struct;

  3. We call btrfs_stop_all_workers() which waits for any jobs running in all
    the work queues and then free the work queues.

Syzbot reported a case where a fixup worker resulted in a crash when doing
a delayed iput on its inode while attempting to wake up the cleaner at
btrfs_add_delayed_iput(), because the task_struct of the cleaner kthread
was already freed. This can happen during unmount because we don't wait
for any fixup workers still running before we call kthread_stop() against
the cleaner kthread, which stops and free all its resources.

Fix this by waiting for any fixup workers at close_ctree() before we call
kthread_stop() against the cleaner and run pending delayed iputs.

The stack traces reported by syzbot were the following:

BUG: KASAN: slab-use-after-free in __lock_acquire+0x77/0x2050 kernel/locking/lockdep.c:5065
Read of size 8 at addr ffff8880272a8a18 by task kworker/u8:3/52

CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.12.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engin…

Source: NIST National Vulnerability Database NVD

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2024-49867 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2024-49867" on the vendor's site.

CVE-2024-49867 (Linux kernel) — CWE-416 / CVSS v3 7.8
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

Use-after-free (CWE-416) exists in Linux kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Linux kernel.

🔥 Severity

Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.

🔧 How to fix

Update to the patched release per vendor advisory.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

  1. 1
    Identify exposure identify 
    Audit SBOM/dependencies for affected components.

    資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。

  2. 2
    Post-deployment verification verify 
    Confirm patched version is live in production

    パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Linux Kernel
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.4.285"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.227"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.6.0"},{"fixed":"5.15.168"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"6.1.113"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.6.55"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.10.14"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.11.3"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

References

We use cookies for analytics and ad measurement. This setting applies to all Game co., Ltd. sites. Details