# CVE-2026-90082: net: mana: Cap MSI-X vectors to the device MSI-X table size

> A missing bounds check in the Linux kernel's mana network driver allows a local attacker to trigger a page fault and system crash by exhausting MSI-X vectors.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-90082, DEBIAN-CVE-2026-90082, GHSA-34r8-cjx6-5m3m, UBUNTU-CVE-2026-90082

## What is CVE-2026-90082?

CVE-2026-90082 is a denial of service vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

net: mana: Cap MSI-X vectors to the device MSI-X table size

mana_gd_query_max_resources() sizes gc->num_msix_usable from resp.max_msix
and the CPU count, but never from the device MSI-X table. On a 1792 vCPU
M-series VM that yields 1793 while the table has 1024 entries, and
mana_gd_setup_remaining_irqs() then walks indices 1..1792, running off the
end of the region mapped by msix_map_region():

  BUG: unable to handle page fault for address: ff8e347f8b99800c
  RIP: 0010:msix_prepare_msi_desc+0x7a/0x90
  RAX: 0000000000004000 RBX: ff4330cb164ea780 RCX: ff8e347f8b998000
  Call Trace:
   <TASK>
   __msi_domain_alloc_irqs+0x13a/0x440
   msi_domain_alloc_irq_at+0x149/0x1b0
   mana_gd_setup+0x351/0x890
   mana_gd_probe+0x274/0x390
   </TASK>

RAX is index 1024 * PCI_MSIX_ENTRY_SIZE, one entry past the table.

msi_insert_desc() does range check the index, but only against the MSI
domain hwsize, which matches the table only for devices on an MSI parent
domain. With a global PCI/MSI domain hwsize is MSI_XA_DOMAIN_SIZE, so
nothing bounds the request.

Cap num_msix_usable with pci_msix_vec_count().

## Which versions are affected by CVE-2026-90082?


## How do I fix CVE-2026-90082?

Apply the vendor's patch.

## Is CVE-2026-90082 being exploited?

There is no known exploitation of CVE-2026-90082 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90082 and fix it if it is affected.

What it is: CVE-2026-90082 is a denial of service vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-90082 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-90082/ (Markdown: https://insights.sbomify.com/CVE-2026-90082/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90082
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90082
- OSV: https://osv.dev/vulnerability/CVE-2026-90082

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90082/
Summaries are generated and may contain mistakes; the official description above is the record.