OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 7.260701.0, the synchronizerFetch GraphQL query called fetchRemoteStreams after checking only that a remote stream URL used HTTP or HTTPS. The backend did not apply the ingestion deny list or reject private, loopback, and link-local destinations, allowing an authenticated account with the INGESTION capability to make OpenCTI request internal services and cloud metadata endpoints. Returned connection errors could distinguish open HTTP ports, open non-HTTP ports, and closed ports, enabling internal network scanning, while compatible endpoint responses could disclose internal data. This issue is fixed in version 7.260701.0.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-918"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76820.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "7.260701.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "6c1114ce8ce8f3a9d9b8c82dfff3a3a462e5dc1f"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "7.260701.0",
"range": [
{
"fixed": "522a28a62155999c76af026f53ede202b934fd0a"
}
],
"source": "REFERENCES_TAG"
}
]
}