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OpenctiApplication · Citeum

CVE-2026-39980

HIGH · 7.2 CVSS v3.1 Published 2026-04-09
Fix available
A fix is available. Upgrade to 6.9.5 or later.
See remediation →
78/100
Remediation priority · High
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

OpenCTI versions prior to 6.9.5 contain a Server-Side Template Injection (SSTI) vulnerability in the safeEjs.ts file. The EJS template engine is not properly sanitized, allowing authenticated users with the 'Manage customization' capability to inject and execute arbitrary JavaScript code within the context of the OpenCTI server process during notifier template execution.

MitigationUpgrade OpenCTI to version 6.9.5 or later. Restrict the 'Manage customization' capability to only trusted administrators until the patch is applied.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
OpenctiApplication
Affected:< 6.9.5

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify OpenCTI version
    Check the installed OpenCTI version via docker ps (container labels), package.json, or the /api/version endpoint if accessible. Compare the version number against the affected range (prior to 6.9.5).
    Affected if The installed version is less than 6.9.5.
  2. Locate vulnerable template file
    Search for the safeEjs.ts file in the OpenCTI installation directory or source code. This file handles EJS template processing and contains the SSTI vulnerability.
    Affected if The safeEjs.ts file exists in the installation and the version is below 6.9.5.
  3. Verify Manage customization capability
    Access the OpenCTI administration panel and navigate to Roles/Permissions. Look for the 'Manage customization' capability in the role definitions.
    Affected if The 'Manage customization' capability exists and is assignable to users.
  4. Check active users with customization access
    Query the OpenCTI database or user management interface to identify users assigned roles that include the 'Manage customization' capability.
    Affected if Any user account has the 'Manage customization' capability enabled.

You are affected if your OpenCTI version is prior to 6.9.5 and any user possesses the 'Manage customization' capability, as they could exploit the SSTI vulnerability in safeEjs.ts.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 6.9.5 or later
Fixed in 6.9.5
Interim mitigation

Upgrade OpenCTI to version 6.9.5 or later. Restrict the 'Manage customization' capability to only trusted administrators until the patch is applied.

Recommended fix High confidence

6.9.5

  1. Back up your current OpenCTI configuration and data before upgrading
  2. Stop the current OpenCTI instance
  3. Update your OpenCTI deployment to version 6.9.5. For Docker Compose, update the image tag in your docker-compose.yml file to '6.9.5'
  4. Pull the new Docker image: docker-compose pull or docker pull opencti/platform:6.9.5
  5. Restart the OpenCTI services: docker-compose up -d
  6. Verify the upgrade by checking the OpenCTI version in the UI or via API
  7. Confirm the safeEjs.ts file has been updated by reviewing the release notes or source code

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Opencti Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,190
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,904.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-39980 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data