# protobufjs has an arbitrary code execution issue

Advisory record · `GHSA-xq3m-2v4x-88gg`

- **Identifiers:** `GHSA-xq3m-2v4x-88gg` · `CVE-2026-41242`
- **State:** Confirmed
- **Severity:** CVSS 9.4 Critical
- **Critical:** Yes: CVSS 9+
- **Weakness (CWE):** [CWE-94](https://cwe.mitre.org/data/definitions/94.html)
- **Tags:** [Code injection](https://agentprime.io/advisories/tag/code-injection.md)
- **Published:** 16 Apr 2026
- **Updated:** 4 Nov 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 16 Apr 2026, 22:34 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Critical

Critical, because:

- CVSS score 9.4: 9.0 or more.

How we decide what’s critical: <https://agentprime.io/advisories/critical.md>

## Affected packages

- `protobufjs` (npm): affected `>=8.0.0, <8.0.1 || >=7.0.0, <7.5.5 || <6.11.6`; fixed in `8.0.1`, `7.5.5`, `6.11.6`

## 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

- 9.4 Critical, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0077, the 56th percentile, on 14 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 16 Apr 2026, 22:34 UTC: [Confirmed by GitHub Advisory Database](https://github.com/advisories/GHSA-xq3m-2v4x-88gg)
- 18 Apr 2026, 16:18 UTC: [Confirmed by the CVE List](https://www.cve.org/CVERecord?id=CVE-2026-41242)
- 18 Apr 2026, 17:16 UTC: [Confirmed by NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-41242)
- 4 Nov 2026, 17:28 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-xq3m-2v4x-88gg)

## Sources

- [GitHub Advisory Database: GHSA-xq3m-2v4x-88gg](https://github.com/advisories/GHSA-xq3m-2v4x-88gg)
- [OSV: GHSA-xq3m-2v4x-88gg](https://osv.dev/vulnerability/GHSA-xq3m-2v4x-88gg)
- <https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-xq3m-2v4x-88gg>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-41242>
- <https://github.com/protobufjs/protobuf.js/commit/ff7b2afef8754837cc6dc64c864cd111ab477956>
- <https://github.com/protobufjs/protobuf.js/commit/535df444ac060243722ac5d672db205e5c531d75>
- <https://github.com/protobufjs/protobuf.js/commit/086916b4a52c9f73ce88956edbb38fc902e54bbf>
- <https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41242.json>
- <https://github.com/protobufjs/protobuf.js/tree/v6.11.6>
- <https://github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v8.0.1>
- <https://github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v7.5.5>
- <https://github.com/protobufjs/protobuf.js>
- <https://bugzilla.redhat.com/show_bug.cgi?id=2459442>
- <https://access.redhat.com/security/cve/CVE-2026-41242>

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-xq3m-2v4x-88gg>, 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-xq3m-2v4x-88gg/>. Everything for agents: <https://agentprime.io/llms.txt>.