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

published 2026-03-12 7 mo ago modified 2026-06-22 4 mo ago also EUVD-2026-11599 , GHSA-ffm6-vvph-g5f5 , PYSEC-2026-118

cvss: 7.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 16%
public exploits: 0; none known

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.

Patch / fix

fixed in 2

pypi pycti 6.8.16
citeum opencti 6.8.16

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 7 mo ago (2026-03-12)

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
GitHub	3.1	7.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
OSV	3.1	7.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

Affected packages

ecosystem	package	affected	fixed in
pypi	pycti	<6.8.16	6.8.16

Affected products

OpenCTI-Platform opencti

Classification

Weakness

CWE-918 Server-Side Request Forgery
CWE-20 Improper Input Validation

References

github.com /OpenCTI-Platform/opencti/security/advisories/GHSA-ffm6-vvph-g5f5
web, vendor-advisory, advisory
nvd.nist.gov /vuln/detail/CVE-2026-21887
advisory
github.com /OpenCTI-Platform/opencti
package
github.com /pypa/advisory-database/tree/main/vulns/pycti/PYSEC-2026-118.yaml
web

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary