CVE-2026-42085

Name: CVE-2026-42085
Creator: NVD / NIST
Published: 2026-05-04T18:16:30.51+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.3/10EPSS 0.31%

Last modified Jun 17, 2026

CVE-2026-42085 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. OpenC3 COSMOS provides the functionality needed to send commands to and receive data from one or more embedded systems. Prior to versions 6.10.5 and 7.0.0-rc3, OpenC3 COSMOS contains a design flaw in the save_tool_config() function that allows saving tool configuration files at arbitrary locations inside the shared /plugins directory tree by supplying crafted configuration filenames. EPSS estimates a 0.31% chance of exploitation in the next 30 days.

Description

OpenC3 COSMOS provides the functionality needed to send commands to and receive data from one or more embedded systems. Prior to versions 6.10.5 and 7.0.0-rc3, OpenC3 COSMOS contains a design flaw in the save_tool_config() function that allows saving tool configuration files at arbitrary locations inside the shared /plugins directory tree by supplying crafted configuration filenames. Although the implementation sufficiently mitigates standard path traversal attacks, by canonicalizing filename to an absolute path, all plugins share this same root directory. That enables users to create arbitrary file structures and overwrite existing configuration files within the shared /plugins directory. This issue has been patched in versions 6.10.5 and 7.0.0-rc3.

Metrics

CVSS 3.1

4.3/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

EPSS Probability

0.31%

23.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-23

Affected Software

Vendor	Product	Versions	Update
Openc3	Cosmos	< 6.10.5	—
Openc3	Cosmos	7.0.0	Rc1

References

https://github.com/OpenC3/cosmos/commit/9957a9fa460c0c0cf5cdbf6a5931bbdd025246a5Patch
https://github.com/OpenC3/cosmos/commit/e6efccbd148ba0e3361c5891027f2373aa140d42Patch
https://github.com/OpenC3/cosmos/releases/tag/v6.10.5Release Notes
https://github.com/OpenC3/cosmos/releases/tag/v7.0.0-rc3Release Notes
https://github.com/OpenC3/cosmos/security/advisories/GHSA-4jvx-93h3-f45hExploit, Vendor Advisory
https://github.com/OpenC3/cosmos/security/advisories/GHSA-4jvx-93h3-f45hExploit, Vendor Advisory

Timeline

Published: May 4, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-42085?

How severe is CVE-2026-42085?

CVE-2026-42085 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 0.31% probability of exploitation in the next 30 days.

How do I fix CVE-2026-42085?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-42085?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST