Linux: Concurrent Execution using Shared Resource with Improper Synchronization
CVE-2026-43353 is a high-severity concurrent execution using shared resource with improper synchronization vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions d2fa9b855c7b42b34b2fb32731bf533952370384, 73bb6b15f1fd71479ed12b314876f3ce5935b80a, 16061383a9def977e4be908c7dcede9a8a4227fd as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.13% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to d2fa9b855c7b42b34b2fb32731bf533952370384 or 73bb6b15f1fd71479ed12b314876f3ce5935b80a or 16061383a9def977e4be908c7dcede9a8a4227fd or b684b420a5bb0ea1b0e13abfdb8ce41c5266e62e, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.18.19 or 6.19.9, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 9ad9a52cce2828d932ae9495181e3d6414f72c07 up to, but not including, d2fa9b855c7b42b34b2fb32731bf533952370384; 9ad9a52cce2828d932ae9495181e3d6414f72c07 up to, but not including, 73bb6b15f1fd71479ed12b314876f3ce5935b80a; 9ad9a52cce2828d932ae9495181e3d6414f72c07 up to, but not including, 16061383a9def977e4be908c7dcede9a8a4227fd; 9ad9a52cce2828d932ae9495181e3d6414f72c07 up to, but not including, b684b420a5bb0ea1b0e13abfdb8ce41c5266e62e; 9ad9a52cce2828d932ae9495181e3d6414f72c07 up to, but not including, 4faa1e9c67a2229f6749190aedaf88ce0391efd2; 9ad9a52cce2828d932ae9495181e3d6414f72c07 up to, but not including, 1dca8aee80eea76d2aae21265de5dd64f6ba0f09; 5.11 | d2fa9b855c7b42b34b2fb32731bf533952370384, 73bb6b15f1fd71479ed12b314876f3ce5935b80a, 16061383a9def977e4be908c7dcede9a8a4227fd, b684b420a5bb0ea1b0e13abfdb8ce41c5266e62e, 4faa1e9c67a2229f6749190aedaf88ce0391efd2, 1dca8aee80eea76d2aae21265de5dd64f6ba0f09 |
| Linux | Linux Kernel | 5.11 up to, but not including, 6.18.19; 6.19 up to, but not including, 6.19.9; 7.0 | 6.18.19, 6.19.9 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: i3c: mipi-i3c-hci: Fix race in DMA ring dequeue The HCI DMA dequeue path (hci_dma_dequeue_xfer()) may be invoked for multiple transfers that timeout around the same time. However, the function is not serialized and can race with itself. When a timeout occurs, hci_dma_dequeue_xfer() stops the ring, processes incomplete transfers, and then restarts the ring. If another timeout triggers a parallel call into the same function, the two instances may interfere with each other - stopping or restarting the ring at unexpected times. Add a mutex so that hci_dma_dequeue_xfer() is serialized with respect to itself.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Concurrent Execution using Shared Resource with Improper Synchronization
The product contains a concurrent code sequence that 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 operating concurrently.
How developers prevent this class of flaw
- In languages that support it, use synchronization primitives. Only wrap these around critical code to minimize the impact on performance.
- Use thread-safe capabilities such as the data access abstraction in Spring.
- Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring. Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
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