CVE-2026-44450CWE-88

Lumiverse: RCE via MCP stdio argument injection

Critical · published May 26, 2026

CVSS v3.1
9.9
EPSS
1%
Percentile
51.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.9 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00677 · 51.7th percentile
Weakness
CWE-88 · Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')
Published
2026-05-26T19:54Z
EPSS history
Timeline
  • 26 MAY 19:54Z
    Lumiverse: RCE via MCP stdio argument injection
    cvelistv5