Command submission hang via publication race
Published Sep 25, 2026 · Updated Sep 25, 2026
Race condition in the Linux 6.13 RISC-V IOMMU command queue allows attackers to hang command submission through concurrent producers. The queue reserves a producer index before writing the command and updating the hardware tail, so failed or reordered publishers leave later submissions waiting behind a gap. Triggering the flaw requires the RISC-V IOMMU command-queue path and concurrent producers; the bounded consequences are a command-submission hang and misleading IOFENCE completion timeouts.
Summary
What happened
Race condition in the Linux 6.13 RISC-V IOMMU command queue allows attackers to hang command submission through concurrent producers. The queue reserves a producer index before writing the command and updating the hardware tail, so failed or reordered publishers leave later submissions waiting behind a gap. Triggering the flaw requires the RISC-V IOMMU command-queue path and concurrent producers; the bounded consequences are a command-submission hang and misleading IOFENCE completion timeouts.
The record
- CVE
- CVE-2026-98004
- Published
- Sep 25, 2026
- Updated
- Sep 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499.004
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 25, 2026CVE publishedPublication date reported by the CVE source.
- Sep 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=6.13
- Affected versionversion=856c0cfe5c5f6a2cc8d995872eb67bff9c68c57c <6d4c12ab9ab8db87411c863a54e0e97f9197afde
- Affected versionversion=856c0cfe5c5f6a2cc8d995872eb67bff9c68c57c <ca58afa40946acd252a50fa4d4a86f15847a3d7d
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
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