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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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
https://github.com/trycua/cua/issues/1892

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-05 10:16

Updated : 2026-09-08 18:21

NVD link : CVE-2026-86121

Mitre link : CVE-2026-86121

CVE.ORG link : CVE-2026-86121

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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