CVE-2026-39980: OpenCTI affected by RCE via notifier template

Published Apr 9, 2026
·
Updated

OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 6.9.5, the safeEjs.ts file does not properly sanitize EJS templates. Users with the Manage customization capability can run arbitrary JavaScript in the context of the OpenCTI platform process during notifier template execution. This vulnerability is fixed in 6.9.5.

Affected Software

2 affected components
OpenCTI OpenCTI<6.9.5
Citeum Opencti<6.9.5

Event History

Apr 9, 2026
CVE Published
via MITRE·04:54 PM
Data Sourced
via MITRE·04:54 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·06:17 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-39980?

CVE-2026-39980 has a high severity due to the potential for remote code execution.

2

How do I fix CVE-2026-39980?

To fix CVE-2026-39980, update OpenCTI to version 6.9.5 or later.

3

Who is affected by CVE-2026-39980?

CVE-2026-39980 affects all versions of OpenCTI prior to 6.9.5.

4

What type of vulnerability is CVE-2026-39980?

CVE-2026-39980 is a remote code execution vulnerability associated with improper sanitization of EJS templates.

5

What can an attacker do with CVE-2026-39980?

An attacker with Manage customization capabilities can execute arbitrary JavaScript on affected systems due to CVE-2026-39980.

Contact

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