---
id: CVE-2026-86121
title: >-
  Cua computer-server versions before 0.3.42 skip authentication when the
  CONTAINER_NAME environment variable is unset and bind to all interfaces by
  default, allowing unauthenticated attackers to execute arbitrary commands
summary: >-
  Cua computer-server versions before 0.3.42 skip authentication when the
  CONTAINER_NAME environment variable is unset and bind to all interfaces by
  default, allowing unauthenticated attackers to execute arbitrary commands.
  Attackers can r…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-306
vendor: trycua
product: cua-computer-server
affected:
  - cua-computer-server < 0.3.42
published: '2026-09-05'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T18:21:14.990'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-86121'
references:
  - url: 'https://github.com/trycua/cua'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py
    label: disclosure@vulncheck.com
  - url: 'https://github.com/trycua/cua/commit/59cf25c0ec54'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/trycua/cua/issues/1892'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control
    label: disclosure@vulncheck.com
  - url: 'https://github.com/trycua/cua/issues/1892'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-09-08T17:25:32.160589Z'
epss: 0.00592
epssPercentile: 0.46992
ingestedAt: '2026-09-06T07:51:56.213Z'
---

## Overview

Cua computer-server versions before 0.3.42 skip authentication when the CONTAINER_NAME environment variable is unset and bind to all interfaces by default, allowing unauthenticated attackers to execute arbitrary commands. Attackers can reach TCP port 8000 to run shell commands via the run_command endpoint, read and write arbitrary files through file operation endpoints, and access interactive PTY shells without authentication.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.