CVE-2026-35210: OpenCTI: Authorization Bypass via `synchronized-upsert` HTTP Header Injection

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• citeum openctibefore 7.260326.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

• OpenCTI-Platform opencti

  • < 7.260326.0affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Other highest-scoring records for the same primary product.

• CVE-2026-27960OpenCTI privilege escalation and unauthenticated access via default admin account
  60This week
• CVE-2026-39980OpenCTI affected by RCE via notifier template
  40Plan
• CVE-2025-61781GraphQL IDOR allows authenticated user to delete workspace content of other users
  36Monitor

Published before and after this one in the same product

• ← EarlierCVE-2026-44730May 26, 2026 · OpenCTI: Privilege escalation via graphQL API abusable by organization admins, due to incorrect ACL on userEdit relationAdd
  28Monitor
• ← EarlierCVE-2026-35212Jun 2, 2026 · OpenCTI has XSS in the rendering of email-message observable body data
  21Monitor
• Later →CVE-2026-35211Jul 8, 2026 · OpenCTI: Elasticsearch Painless Script Injection via GraphQL `script` filter operator allows authenticated user to exfiltrate data and cause DoS
  26Monitor

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

The endpoint fetches the record by the ID sent in the request, but never checks whether the record belongs to the requesting user.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1const invoice = await Invoice.findById(req.params.id);2res.json(invoice);

1const invoice = await Invoice.findOne({2  id: req.params.id,3  ownerId: req.user.id,4});5if (!invoice) return res.sendStatus(404);6res.json(invoice);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.