Linux Kernel up to 7.2.13 io-wq io_uring io_wq_exit_workers race condition

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k0.43-

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.1.190/6.6.160/6.12.114/6.18.59/7.2.13. This issue affects the function io_wq_exit_workers of the file io_uring of the component io-wq. The manipulation results in race condition. This vulnerability is identified as CVE-2026-99228. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.1.190/6.6.160/6.12.114/6.18.59/7.2.13. Affected is the function io_wq_exit_workers of the file io_uring of the component io-wq. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: io_uring/io-wq: don't lose the signal that ends work When a thread exits, only its tracked requests are cancelled. Then its io-wq is torn down. io_wq_exit_workers() signals every worker, to get it out of an interruptible sleep, and waits for all of them to exit. Before they do, they go through the work that is left. Unbounded work is cancelled. Bounded work is run, as it is expected to end by itself. Not all of it does. An open has no file yet, so it counts as bounded, and the open of a FIFO waits for the other end. That is what the signal is for. But the workers are signalled once, and a worker that hasn't started the work by then loses the signal: io_wq_exit_workers() io_worker_handle_work() io_wq_worker_wake() set TIF_NOTIFY_SIGNAL io_assign_current_work() io_run_task_work() clear TIF_NOTIFY_SIGNAL io_wq_submit_work() fifo_open() wait_for_partner() wait_for_completion_timeout() The thread never gets out of do_exit(): IORING_OP_OPENAT of a FIFO without a writer, IOSQE_ASYNC exit of the thread that has submitted it hangs in more than 9 of 10 attempts (4 CPUs, KVM), until the process is killed. Set TIF_NOTIFY_SIGNAL for bounded work that is started with IO_WQ_BIT_EXIT set. The bit is set before the workers are signalled, and it is tested after the flag has been cleared, with clear_notify_signal() providing the barrier. So either the flag stays, or the bit is seen. Work that is started while the io-wq exits is treated like work that is being run at that time: it isn't interrupted unless it waits interruptibly.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-99228 since 09/25/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 11/02/2026).

Upgrading to version 6.1.191, 6.6.161, 6.12.115, 6.18.60 or 7.2.14 eliminates this vulnerability. Applying the patch ddccc60f036b309430cf130d48aafed94ef7355a/08c42055b8f9a5d29236d34ad4bce08828239fe1/62996803c1b5f18176de255db4c843021f2d19c8/7309fea05a3d66af9746843c43fef14c10b8141e/fdb771015c1e13677b57a4015f0c938748f13781 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.191/6.6.161/6.12.115/6.18.60/7.2.14
Patch: ddccc60f036b309430cf130d48aafed94ef7355a/08c42055b8f9a5d29236d34ad4bce08828239fe1/62996803c1b5f18176de255db4c843021f2d19c8/7309fea05a3d66af9746843c43fef14c10b8141e/fdb771015c1e13677b57a4015f0c938748f13781

Timelineinfo

09/25/2026 CVE reserved
11/02/2026 +38 days Advisory disclosed
11/02/2026 +0 days VulDB entry created
11/02/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CNA: Linux
CVE: CVE-2026-99228 (🔒)

GCVE (CVE): GCVE-0-2026-99228
GCVE (VulDB): GCVE-100-429906

Entryinfo

Created: 11/02/2026 17:23
Changes: 11/02/2026 17:23 (60)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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