{"id":"CVE-2026-21887","aliases":["GHSA-ffm6-vvph-g5f5","PYSEC-2026-118"],"url":"https://o3.security/vulnerability/CVE-2026-21887","summary":"OpenCTI has a Semi-Blind SSRF via Unvalidated External URL in Data Ingestion Feature","details":"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.","published":"2026-03-12T17:00:43.944Z","modified":"2026-08-12T03:51:30.140032532Z","cvss":{"score":7.7,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N"},"epss":{"score":0.00212,"percentile":0.11718,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"pycti","fixedVersion":"6.8.16"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21887.json"},{"type":"ADVISORY","url":"https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-ffm6-vvph-g5f5"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-21887"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:30.140032532Z"}}