CVE-2025-26621

mediumpriority · track · 27EPSS 0.004 · 36 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.42% (36th) EPSS

CVSS 6.8 · medium

Is it mine?

5 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.2–7.6

v3.16.8mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.3 · impact 4

v3.17.6highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:Hsecondary · ENISA EU

v3.17.6highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:Hsecondary · security-advisories@github.comexploitability 2.3 · impact 4.7

v3.16.8mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:Hsecondary · OSV

v3.16.2mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1321USprimaryCWE-94US

affected products (5)

Products and version ranges known to be affected.

Open Source OpenCTI <6.5.2all versionscert_bundDE
Open Source OpenCTI< 6.5.2cert_bundDE
OpenCTI-Platform opencti≤ < 6.5.2enisa_euvdEU
citeum opencti< 6.5.2nvdUScpe:2.3:a:citeum:opencti:*:*:*:*:*:*:*:*
PyPI pycti< 6.5.2osvUSpkg:pypi/pycti

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-1102OpenCTI: Schwachstelle ermöglicht Denial of ServiceDeutsch2025-05-19csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in OpenCTI ausnutzen, um einen Denial of Service Angriff durchzuführen.
PYSEC-2025-1802025-05-19vendor · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd osv NVD CVE.org MITRE

published 2025-05-19modified 2026-06-17

related (708)

Related entries.

ID	severity	EPSS	exploitable	published
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Apache Struts 2.0.0 to 2.5.20 forced double OGNL evaluation, when evaluated on raw user input in tag attributes, may lead to remote code execution.
CVE-2022-24760US	critical10.0	49.4% (99th)	Exploit	2022-03-12
Parse Server is an open source http web server backend. In versions prior to 4.10.7 there is a Remote Code Execution (RCE) vulnerability in Parse Server. This vulnerability affects…
CVE-2019-11358US	medium6.1	86.8% (100th)	Exploit	2019-04-20
jQuery before 3.4.0, as used in Drupal, Backdrop CMS, and other products, mishandles jQuery.extend(true, {}, ...) because of Object.prototype pollution. If an unsanitized source ob…
CVE-2020-7774US	critical9.8	69.4% (99th)	—	2020-11-17
The package y18n before 3.2.2, 4.0.1 and 5.0.5, is vulnerable to Prototype Pollution.

+703 more

references (7)

External citations — patches, advisories, analysis.

scry

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