CVE-2026-21887
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).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.21%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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 3.1
- 7.7 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
- EPSS
- 0.21% probability · 12th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-918
- Affected
- citeum/opencti
- Source
- security-advisories@github.com
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.