Linux Kernel up to 7.2.4 qla2xxx qla_calc_queue_count msix_count null pointer dereference

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 7.8 | $0-$5k | 0.00+ |
Summary
A vulnerability identified as very critical has been detected in Linux Kernel up to 7.2.4. This issue affects the function qla_calc_queue_count of the component qla2xxx. This manipulation of the argument msix_count causes null pointer dereference.
This vulnerability appears as CVE-2026-89856. The attack requires local access. There is no available exploit.
You should upgrade the affected component.
Details
A vulnerability was found in Linux Kernel up to 7.2.4. It has been declared as very critical. Affected by this vulnerability is the function qla_calc_queue_count of the component qla2xxx. The manipulation of the argument msix_count with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:
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).
The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2026-89856 since 09/11/2026. The exploitation appears to be easy. An attack has to be approached locally. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/16/2026).
Upgrading to version 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, 6.18.51, 7.2.5 or 7.3-rc1 eliminates this vulnerability. Applying the patch cf623d32761b00f221a9cfded3303d56e84b429d/9eeddbeaa896f39d943644b16d83a6ad0ceab255/802068b9b683b8008fcccbf6e9ad133e597ec87c/e80adfeac61b4d5db7ffe0f5af43999c33a4145e/2efe50b2da829909023de4a2eb87badb7cfa53cc/7a448f5ed0b283dbde4e9183dd1e98c221432dab/33c77254e6e91f37c72c7fad4051777452b10de8/ebfd35c64433821bd5619a6d07ccc2df8b5b1de3 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Product
Type
Vendor
Name
Version
- 5.10.269
- 5.15.220
- 6.1.187
- 6.6.156
- 6.12.109
- 6.18.0
- 6.18.1
- 6.18.2
- 6.18.3
- 6.18.4
- 6.18.5
- 6.18.6
- 6.18.7
- 6.18.8
- 6.18.9
- 6.18.10
- 6.18.11
- 6.18.12
- 6.18.13
- 6.18.14
- 6.18.15
- 6.18.16
- 6.18.17
- 6.18.18
- 6.18.19
- 6.18.20
- 6.18.21
- 6.18.22
- 6.18.23
- 6.18.24
- 6.18.25
- 6.18.26
- 6.18.27
- 6.18.28
- 6.18.29
- 6.18.30
- 6.18.31
- 6.18.32
- 6.18.33
- 6.18.34
- 6.18.35
- 6.18.36
- 6.18.37
- 6.18.38
- 6.18.39
- 6.18.40
- 6.18.41
- 6.18.42
- 6.18.43
- 6.18.44
- 6.18.45
- 6.18.46
- 6.18.47
- 6.18.48
- 6.18.49
- 6.18.50
- 7.2.0
- 7.2.1
- 7.2.2
- 7.2.3
- 7.2.4
License
Website
- Vendor: https://www.kernel.org/
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔒VulDB Reliability: 🔍
CVSSv3
VulDB Meta Base Score: 8.2VulDB Meta Temp Score: 7.8
VulDB Base Score: 8.2
VulDB Temp Score: 7.8
VulDB Vector: 🔒
VulDB Reliability: 🔍
CVSSv2
| AV | AC | Au | C | I | A |
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| 💳 | 💳 | 💳 | 💳 | 💳 | 💳 |
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| Vector | Complexity | Authentication | Confidentiality | Integrity | Availability |
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| Unlock | Unlock | Unlock | Unlock | Unlock | Unlock |
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
Exploiting
Class: Null pointer dereferenceCWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒
Physical: Partially
Local: Yes
Remote: Partially
Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒
| 0-Day | Unlock | Unlock | Unlock | Unlock |
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| Today | Unlock | Unlock | Unlock | Unlock |
Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: UpgradeStatus: 🔍
0-Day Time: 🔒
Upgrade: Kernel 5.10.270/5.15.221/6.1.188/6.6.157/6.12.110/6.18.51/7.2.5/7.3-rc1
Patch: cf623d32761b00f221a9cfded3303d56e84b429d/9eeddbeaa896f39d943644b16d83a6ad0ceab255/802068b9b683b8008fcccbf6e9ad133e597ec87c/e80adfeac61b4d5db7ffe0f5af43999c33a4145e/2efe50b2da829909023de4a2eb87badb7cfa53cc/7a448f5ed0b283dbde4e9183dd1e98c221432dab/33c77254e6e91f37c72c7fad4051777452b10de8/ebfd35c64433821bd5619a6d07ccc2df8b5b1de3
Timeline
09/11/2026 CVE reserved09/16/2026 Advisory disclosed
09/16/2026 VulDB entry created
09/16/2026 VulDB entry last update
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2026-89856 (🔒)
GCVE (CVE): GCVE-0-2026-89856
GCVE (VulDB): GCVE-100-405673
Entry
Created: 09/16/2026 13:39Changes: 09/16/2026 13:39 (60)
Complete: 🔍
Cache ID: 216::103
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
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