# CVE-2026-52968: KVM: s390: pci: fix GAIT table indexing due to double-scaling pointer arithmetic

> Out-of-bounds memory access in Linux kernel KVM s390 PCI code due to incorrect pointer arithmetic, potentially allowing code execution or denial of service.

- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Jun 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-52968, DEBIAN-CVE-2026-52968, GHSA-8vvj-3j37-6m3p, ROOT-OS-DEBIAN-12-CVE-2026-52968, ROOT-OS-UBUNTU-2204-CVE-2026-52968, ROOT-OS-UBUNTU-2404-CVE-2026-52968, UBUNTU-CVE-2026-52968

## What is CVE-2026-52968?

CVE-2026-52968 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 Jun 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:

KVM: s390: pci: fix GAIT table indexing due to double-scaling pointer arithmetic

kvm_s390_pci_aif_enable(), kvm_s390_pci_aif_disable(), and
aen_host_forward() index the GAIT by manually multiplying the index
with sizeof(struct zpci_gaite).

Since aift->gait is already a struct zpci_gaite pointer, this
double-scales the offset, accessing element aisb*16 instead of aisb.

This causes out-of-bounds accesses when aisb >= 32 (with
ZPCI_NR_DEVICES=512)

Fix by removing the erroneous sizeof multiplication.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-52968?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-52968?

Apply the vendor's patch.

## Is CVE-2026-52968 being exploited?

There is no known exploitation of CVE-2026-52968 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-52968 and fix it if it is affected.

What it is: CVE-2026-52968 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 Jun 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-2026-52968 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-52968/ (Markdown: https://insights.sbomify.com/CVE-2026-52968/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-52968
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-52968
- OSV: https://osv.dev/vulnerability/CVE-2026-52968

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-52968/
Summaries are generated and may contain mistakes; the official description above is the record.