OpenCTI up to 6.8.15 server-side request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.8$0-$5k0.00

Summaryinfo

A vulnerability was found in OpenCTI up to 6.8.15. It has been rated as critical. This affects an unknown function. Performing a manipulation results in server-side request forgery. This vulnerability is identified as CVE-2026-21887. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in OpenCTI up to 6.8.15. This affects an unknown function. The manipulation with an unknown input leads to a server-side request forgery vulnerability. CWE is classifying the issue as CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 6.8.16, the OpenCTI platform’s data ingestion feature accepts user-supplied URLs without validation and uses the Axios HTTP client with its default configuration (allowAbsoluteUrls: true). This allows attackers to craft requests to arbitrary endpoints, including internal services, because Axios will accept and process absolute URLs. This results in a semi-blind SSRF, as responses may not be fully visible but can still impact internal systems. This vulnerability is fixed in 6.8.16.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-21887 since 01/05/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Neither technical details nor an exploit are publicly available.

Upgrading to version 6.8.16 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0715). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Open Source OpenCTI

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.8

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.7
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: OpenCTI 6.8.16

Timelineinfo

01/05/2026 CVE reserved
03/12/2026 +66 days Advisory disclosed
03/12/2026 +0 days VulDB entry created
03/19/2026 +7 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-ffm6-vvph-g5f5
Status: Confirmed

CVE: CVE-2026-21887 (🔒)
GCVE (CVE): GCVE-0-2026-21887
GCVE (VulDB): GCVE-100-350721
CERT Bund: WID-SEC-2026-0715 - OpenCTI: Schwachstelle ermöglicht Offenlegung von Informationen

Entryinfo

Created: 03/12/2026 18:26
Updated: 03/19/2026 23:58
Changes: 03/12/2026 18:26 (63), 03/14/2026 00:08 (7), 03/19/2026 23:58 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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