high7.7
CVE-2026-21887
OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables.
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | pycti | < 6.8.16 | 6.8.16 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Citeum | Opencti | before 6.8.16 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-ffm6-vvph-g5f5
- https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-ffm6-vvph-g5f5
- https://nvd.nist.gov/vuln/detail/CVE-2026-21887
- https://github.com/pypa/advisory-database/tree/main/vulns/pycti/PYSEC-2026-118.yaml