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CVE

CVE-2026-21887

OpenCTI has a Semi-Blind SSRF via Unvalidated External URL in Data Ingestion Feature
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CVE

CVE-2026-21887

OpenCTI has a Semi-Blind SSRF via Unvalidated External URL in Data Ingestion Feature

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.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
7.7
-
3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
C
H
U
-

Related Resources

No items found.

References

https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21887.json, https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-ffm6-vvph-g5f5, https://nvd.nist.gov/vuln/detail/CVE-2026-21887

Severity

7.7

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
7.7
EPSS Probability
0.00044%
EPSS Percentile
0.13625%
Introduced Version
0
Fix Available
177a74ff8807327134c793af8784a96dd4182fbd

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