9.8
CRITICAL CVSS 3.1
CVE-2026-86121
Cua computer-server before 0.3.42 Unauthenticated RCE via Desktop Control
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.

INFO

Published Date :

Sept. 5, 2026, 10:16 a.m.

Last Modified :

Sept. 5, 2026, 10:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-86121 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 CRITICAL [email protected]
CVSS 4.0 CRITICAL 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 CRITICAL [email protected]
Solution
Update Cua computer-server to version 0.3.42 or later to fix authentication bypass.
  • Update Cua computer-server to version 0.3.42 or later.
  • Ensure the CONTAINER_NAME environment variable is always set.
  • Restrict access to TCP port 8000.
  • Review and secure file operation endpoints.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-86121 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-86121 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-86121 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 05, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-306
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/86xxx/CVE-2026-86121.json">CVE-2026-86121</a>
    Added Reference https://github.com/trycua/cua
    Added Reference https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/cli.py
    Added Reference https://github.com/trycua/cua/blob/10a2e71792db/libs/python/computer-server/computer_server/main.py
    Added Reference https://github.com/trycua/cua/commit/59cf25c0ec54
    Added Reference https://github.com/trycua/cua/issues/1892
    Added Reference https://www.vulncheck.com/advisories/cua-computer-server-before-0.3.42-unauthenticated-rce-via-desktop-control
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.