Kernel crash via truncated MSI-X queue count
Published Sep 16, 2026 · Updated Sep 16, 2026
Integer truncation in Linux qla2xxx allows physically proximate attackers to crash the kernel through crafted MSI-X vector counts. Queue derivation stores msix_count minus one in u8 fields, so values of 1 or 257 become zero; qla2x00_alloc_queues then accepts ZERO_SIZE_PTR and writes through it. Exploitation requires a QLogic-compatible board or malicious hot-plugged device advertising the triggering vector count, and the result is kernel memory corruption or a crash.
Summary
What happened
Integer truncation in Linux qla2xxx allows physically proximate attackers to crash the kernel through crafted MSI-X vector counts. Queue derivation stores msix_count minus one in u8 fields, so values of 1 or 257 become zero; qla2x00_alloc_queues then accepts ZERO_SIZE_PTR and writes through it. Exploitation requires a QLogic-compatible board or malicious hot-plugged device advertising the triggering vector count, and the result is kernel memory corruption or a crash.
The record
- CVE
- CVE-2026-89856
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 16, 2026CVE publishedPublication date reported by the CVE source.
- Sep 16, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=4.10
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <2efe50b2da829909023de4a2eb87badb7cfa53cc
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <33c77254e6e91f37c72c7fad4051777452b10de8
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <7a448f5ed0b283dbde4e9183dd1e98c221432dab
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <802068b9b683b8008fcccbf6e9ad133e597ec87c
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <9eeddbeaa896f39d943644b16d83a6ad0ceab255
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <cf623d32761b00f221a9cfded3303d56e84b429d
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <e80adfeac61b4d5db7ffe0f5af43999c33a4145e
- Affected versionversion=d74595278f4ab192af66d9e60a9087464638beee <ebfd35c64433821bd5619a6d07ccc2df8b5b1de3
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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