CVE-2026-86121

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.

Score

CVSS 3.1 9.8 Critical

Status

Deferred - disclosure@vulncheck.com

Published

2026-09-05

Last modified

2026-09-24

Weaknesses

CWE-306

Affected products

• Cua-computer-server (Trycua)

References

• https://github.com/trycua/cua
• https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py
• https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py
• https://github.com/trycua/cua/commit/59cf25c0ec54
• https://github.com/trycua/cua/issues/1892
• https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control