# CVE-2026-89856: scsi: qla2xxx: Clamp MSI-X derived queue counts to avoid truncation

CVE-2026-89856 is fixed in 47 products on 1 platform, first by DEBIAN-CVE-2026-89856, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-89856
- Priority: High
- CVSS: 8.4 (Important)
- EPSS: 0.0019
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 16, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-89856

## Description

In the Linux kernel, the following vulnerability has been resolved:  scsi: qla2xxx: Clamp MSI-X derived queue counts to avoid truncation  ha->msix_count is u16, but ha->max_req_queues, ha->max_rsp_queues and ha->max_qpairs are u8. Deriving the queue count as "ha->max_req_queues = ha->msix_count - 1" therefore truncates: a board (or a misconfigured/malicious hot-plugged device) advertising 257 MSI-X vectors yields msix_count - 1 == 256, which truncates to 0. An MSI-X count of 1 zeroes it as well, and in target mode the subsequent "ha->max_req_queues--" then underflows 0 to 255.  When the count is 0, qla2x00_alloc_queues() calls kzalloc_objs(struct req_que *, 0), which returns ZERO_SIZE_PTR. That is not NULL, so the allocation check passes and the following "ha->req_q_map[0] = req" dereferences ZERO_SIZE_PTR, corrupting memory or crashing the kernel.  Add qla_calc_queue_count() to clamp the derived value into [1, QLA_MAX_QUEUES - 1] so it always fits in u8 and is never zero, and use it at all three derivation sites (qla25xx_iospace_config(), qla83xx_iospace_config() and qla24xx_enable_msix()). Also guard the target-mode decrement so it cannot reintroduce a zero (which would in turn underflow max_qpairs).

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | kernel-64kb sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-azure sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-default sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-default-base sles 15.7 | 6.4.0-150700.53.90.1.150700.17.51.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-docs sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-livepatch-SLE15-SP7_Update_24 sles 15.7 | 1-150700.15.3.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-obs-build sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-source sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-syms sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | kernel-uek ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-devel ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-devel ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-deprecated ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-deprecated ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-desktop ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-desktop ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra-netfilter ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra-netfilter ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-usb ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-usb ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-wireless ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-wireless ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-devel ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-devel ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-doc ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-doc ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-deprecated ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-deprecated ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-desktop ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-desktop ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra-netfilter ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra-netfilter ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-usb ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-usb ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-wireless ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-wireless ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-tools ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-tools ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-devel ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-devel ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-deprecated ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-deprecated ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-desktop ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-desktop ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra-netfilter ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra-netfilter ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-usb ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-usb ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-wireless ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-wireless ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-zfcpdump sles 15.7 | 6.4.0-150700.53.90.1 | [SUSE-SU-2026:5091-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-5091-1.md) | Nov 7, 2026 |
| Linux | linux Debian 12.15 (bookworm) | 6.1.190-1 | [DEBIAN-CVE-2026-89856](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89856.md) | Sep 23, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.111-1 | [DEBIAN-CVE-2026-89856](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89856.md) | Sep 23, 2026 |
| Linux | linux Debian 14 | 7.2.6-1 | [DEBIAN-CVE-2026-89856](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89856.md) | Sep 23, 2026 |
| Linux | linux-6.12 Debian 12.15 (bookworm) | 6.12.111-1~deb12u1 | [DEBIAN-CVE-2026-89856](https://patchblox.com/security/data/fix/linux/debian-cve-2026-89856.md) | Sep 23, 2026 |

---

Data as of 2026-11-09T13:31:49Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.