CVE-2024-56709
CVE-2024-56709 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- EPSS exploit prediction: 0% (11th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2024-53357
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: io_uring: check if iowq is killed before queuing task work can be executed after the task has gone through io_uring termination, whether it's the final task_work run or the fallback path. In this case, task work will find ->io_wq being already killed and null'ed, which is a problem if it then tries to forward the request to io_queue_iowq(). Make io_queue_iowq() fail requests in this case. Note that it also checks PF_KTHREAD, because the user can first close a DEFER_TASKRUN ring and shortly after kill the task, in which case ->iowq check would race.
Frequently asked questions
- What is CVE-2024-56709?
- In the Linux kernel, the following vulnerability has been resolved: io_uring: check if iowq is killed before queuing task work can be executed after the task has gone through io_uring termination, whether it's the final task_work run or the fallback path. In this case, task work will find ->io_wq being already killed and null'ed, which is a problem if it then tries to forward the request to io_queue_iowq(). Make io_queue_iowq() fail requests in this case. Note that it also checks PF_KTHREAD, because the user can first close a DEFER_TASKRUN ring and shortly after kill the task, in which case ->iowq check would race.
- How severe is CVE-2024-56709?
- CVE-2024-56709 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2024-56709 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2024-56709?
- CVE-2024-56709 primarily affects Linux Linux Kernel. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2024-56709?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2024-56709 have an EU (EUVD) identifier?
- Yes. CVE-2024-56709 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-53357.
- When was CVE-2024-56709 published?
- CVE-2024-56709 was published on 2024-12-29 and last updated on 2026-06-17.
References
- https://git.kernel.org/stable/c/2ca94c8de36091067b9ce7527ae8db3812d38781
- https://git.kernel.org/stable/c/4f95a2186b7f2af09331e1e8069bcaf34fe019cf
- https://git.kernel.org/stable/c/534d59ab38010aada88390db65985e65d0de7d9e
- https://git.kernel.org/stable/c/dbd2ca9367eb19bc5e269b8c58b0b1514ada9156
- https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
Affected products (9)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.14:-:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.14:rc4:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.14:rc5:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.14:rc6:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.14:rc7:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*
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