CVE-2026-21887

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.

CVSS v3 7.7 HIGH

7.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.1 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-ffm6-vvph-g5f5	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:citeum:opencti:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-12 17:16

Updated : 2026-03-19 17:39

NVD link : CVE-2026-21887

Mitre link : CVE-2026-21887

CVE.ORG link : CVE-2026-21887

JSON object : View

Products Affected

citeum

opencti

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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