CVE-2025-26621: opencti Code Injection — Fix

Description

OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to version 6.5.2, any user with the capability manage customizations can edit webhook that will execute javascript code. This can be abused to cause a denial of service attack by prototype pollution, making the node js server running the OpenCTI frontend become unavailable. Version 6.5.2 fixes the issue.

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CVSS v3.1 Score

7.6

HIGH

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

Weakness Type (CWE)

CWE-94 CWE-94

CWE-1321 CWE-1321

Affected Products

Vendor	Product	Versions
citeum	opencti	< 6.5.2

References

Advisories & Patches

https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-gq63-jm3h-374p

Other References

https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-mf88-g2wq-p7qm

Frequently Asked Questions

What is CVE-2025-26621? +

OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to version 6.5.2, any user with the capability manage customizations can edit webhook that will execute javascript code. This can be abused to cause a denial of service attack by prototype pollution, making the node js server running the OpenCTI frontend become unavailable. Version 6.5.2 fixes the issue. It has a CVSS v3.1 base score of 7.6 (HIGH).

How severe is CVE-2025-26621? +

CVE-2025-26621 has a CVSS v3.1 score of 7.6 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-26621? +

CVE-2025-26621 affects products from citeum, specifically: opencti. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-26621? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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