Vulnerability · Published Sep 5, 2026 · Assigned by VulnCheck

CVE-2026-86121Cua computer-server before 0.3.42 Unauthenticated RCE via Desktop Control

Critical 9.8

In plain English

A critical-severity missing authentication in cua-computer-server from trycua. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 66% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical

Exploit odds (30 days)1.1%top 33.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
trycua	cua-computer-server	0 – before 0.3.42

Weakness: CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

GitHub Issue #1892 issue-tracking
Server.auth allow-all when CONTAINER_NAME is unset technical-description
CLI --host default of 0.0.0.0 technical-description
Bind default changed to 127.0.0.1 patch
https://github.com/trycua/cua product
VulnCheck Advisory: Cua computer-server before 0.3.42 Unauthenticated RCE via Desktop Control third-party-advisory