Linux: Concurrent Execution using Shared Resource with Improper Synchronization
CVE-2026-68417 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 3c9d128219964dcea897bf6139b88242e987be8f, 3ff82e3841ecab1ff38d5817c969a019d266c83c, 36e91a58397ca8c978e38a0bf389f0c6113fa8ca 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 0.1% 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 3c9d128219964dcea897bf6139b88242e987be8f or 3ff82e3841ecab1ff38d5817c969a019d266c83c or 36e91a58397ca8c978e38a0bf389f0c6113fa8ca or 74912ad168f87d6b2b670a87987bb302d6e64aa1, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | f29dd55b0236f7a26a4b9dd69186e3c04266797b up to, but not including, 3c9d128219964dcea897bf6139b88242e987be8f; f29dd55b0236f7a26a4b9dd69186e3c04266797b up to, but not including, 3ff82e3841ecab1ff38d5817c969a019d266c83c; f29dd55b0236f7a26a4b9dd69186e3c04266797b up to, but not including, 36e91a58397ca8c978e38a0bf389f0c6113fa8ca; f29dd55b0236f7a26a4b9dd69186e3c04266797b up to, but not including, 74912ad168f87d6b2b670a87987bb302d6e64aa1; f29dd55b0236f7a26a4b9dd69186e3c04266797b up to, but not including, fcc9d50022bcdb1f9f7ed04955c72b4a7355af3d; f29dd55b0236f7a26a4b9dd69186e3c04266797b up to, but not including, 52f9fcb191143448df55fd215ff09c5207fed43e; f29dd55b0236f7a26a4b9dd69186e3c04266797b up to, but not including, bb27fcc67c429d97f785c92c35a6c5adebb05d7f; 5.3 | 3c9d128219964dcea897bf6139b88242e987be8f, 3ff82e3841ecab1ff38d5817c969a019d266c83c, 36e91a58397ca8c978e38a0bf389f0c6113fa8ca, 74912ad168f87d6b2b670a87987bb302d6e64aa1, fcc9d50022bcdb1f9f7ed04955c72b4a7355af3d, 52f9fcb191143448df55fd215ff09c5207fed43e |
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: RDMA/siw: publish QP after initialization siw_create_qp() currently calls siw_qp_add() before the queues, CQ pointers, state, completion, and device list entry are ready. A QPN lookup can therefore reach a QP that is still being constructed. Move siw_qp_add() to the end of siw_create_qp(), after QP initialization and before adding the QP to the siw device list.
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.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
- git.kernel.org/stable/c/36e91a58397ca8c978e38a0bf389f0c6113fa8ca
- git.kernel.org/stable/c/3c9d128219964dcea897bf6139b88242e987be8f
- git.kernel.org/stable/c/3ff82e3841ecab1ff38d5817c969a019d266c83c
- git.kernel.org/stable/c/52f9fcb191143448df55fd215ff09c5207fed43e
- git.kernel.org/stable/c/74912ad168f87d6b2b670a87987bb302d6e64aa1
- git.kernel.org/stable/c/bb27fcc67c429d97f785c92c35a6c5adebb05d7f
- git.kernel.org/stable/c/fcc9d50022bcdb1f9f7ed04955c72b4a7355af3d
Recent Concurrent Execution using Shared Resource with Improper Synchronization vulnerabilities
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- 7.8 High severity
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