# ONNX: Null Pointer Dereference in ScanInferenceFunction Due to Missing Required Attribute

Advisory record · `GHSA-m4pr-6v3c-6fgr`

- **Identifiers:** `GHSA-m4pr-6v3c-6fgr` · `CVE-2026-115921`
- **State:** Confirmed
- **Severity:** CVSS 6.2 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-195](https://cwe.mitre.org/data/definitions/195.html) · [CWE-476](https://cwe.mitre.org/data/definitions/476.html)
- **Tags:** [Memory corruption](https://agentprime.io/advisories/tag/memory-corruption.md) · [CWE-195](https://agentprime.io/advisories/tag/cwe-195.md)
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 28 Oct 2026, 21:16 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `onnx` (PyPI): affected `>=1.4.0, <1.22.0`; fixed in `1.22.0`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> GHSA-m4pr-6v3c-6fgr affects the PyPI package onnx from 1.4.0 before 1.22.0, where Scan shape inference mishandled the required num_scan_inputs attribute. A missing attribute caused a null pointer dereference, and a negative value led to a large allocation failure that raised an exception. An attacker who supplies a malicious model to an application that runs shape inference on it can crash the process, which is a denial of service; no confidentiality or integrity impact was demonstrated. Upgrade to onnx 1.22.0 or later.

Written 31 Oct 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 6.2 Medium, CVSS 3.1: `CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0013, the 2nd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 26 Oct 2026, 17:28 UTC: [Confirmed by the CVE List](https://www.cve.org/CVERecord?id=CVE-2026-115921)
- 31 Oct 2026, 14:07 UTC: First seen by agentprime
- 31 Oct 2026, 14:07 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-m4pr-6v3c-6fgr)

## Sources

- [GitHub Advisory Database: GHSA-m4pr-6v3c-6fgr](https://github.com/advisories/GHSA-m4pr-6v3c-6fgr)
- [OSV: GHSA-m4pr-6v3c-6fgr](https://osv.dev/vulnerability/GHSA-m4pr-6v3c-6fgr)
- <https://github.com/onnx/onnx/security/advisories/GHSA-m4pr-6v3c-6fgr>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-115921>
- <https://github.com/onnx/onnx/pull/7916>
- <https://github.com/onnx/onnx/commit/dd6bc92ea39fd2274fd671f0734b0b8b558356f5>
- <https://github.com/onnx/onnx>
- <https://github.com/onnx/onnx/releases/tag/v1.22.0>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-m4pr-6v3c-6fgr>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-m4pr-6v3c-6fgr/>. Everything for agents: <https://agentprime.io/llms.txt>.