# CVE-2026-84286: OOB Read/Write via Negative Array Index in exllamav3_ext Kernel Table

> A malicious model can trigger out-of-bounds memory access in ExLlamaV3, potentially leading to code execution or crashes during model loading.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** GHSA-mw4q-pwhm-35f7

## What is CVE-2026-84286?

CVE-2026-84286 is a critical memory corruption vulnerability in Turboderp-org ExLlamaV3, published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

ExLlamaV3’s EXL3 loader uses an untrusted, model-supplied index to select a CUDA kernel without first verifying that the index is within bounds. A malicious model can force the code to read and invoke an out‑of‑range function pointer, resulting in a reproducible crash. Under specific conditions involving certain host memory layouts, it may be possible for an attacker to exploit this vulnerability to achieve controlled indirect kernel dispatch during model load.

Weakness: CWE-787 (Out-of-bounds Write), CWE-20 (Improper Input Validation), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-84286?


## How do I fix CVE-2026-84286?

No fix has been published for CVE-2026-84286 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-84286 being exploited?

There is no known exploitation of CVE-2026-84286 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-84286 and fix it if it is affected.

What it is: CVE-2026-84286 is a critical memory corruption vulnerability in Turboderp-org ExLlamaV3, published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-84286 in the wild and no public exploit code.

Affected product: Turboderp-org ExLlamaV3. 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-2026-84286/ (Markdown: https://insights.sbomify.com/CVE-2026-84286/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-84286
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-84286
- OSV: https://osv.dev/vulnerability/CVE-2026-84286

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-84286/
Summaries are generated and may contain mistakes; the official description above is the record.