Vulnerability · Published Jul 8, 2026 · Assigned by GitHub_M
CVE-2026-35210OpenCTI: Authorization Bypass via `synchronized-upsert` HTTP Header Injection
High 7.1
In plain English
A high-severity authorization bypass via user-controlled key in opencti from OpenCTI-Platform. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 7.260326.0, an authorization bypass vulnerability in OpenCTI allows any authenticated user with KNOWLEDGE_KNUPDATE permission to bypass Confidence Level validation and Object Marking restrictions by injecting the synchronized-upsert: true HTTP header, enabling attackers to downgrade confidence levels, remove security markings such as TLP:RED, manipulate relationships, and affect STIX object types including Indicators, ThreatActors, Malware, and Reports. This issue is fixed in version 7.260326.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | pycti | 7.260326.0 | PYSEC-2026-3445 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| OpenCTI-Platform | opencti | < 7.260326.0 |
Weakness: CWE-639, CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
References
- https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-36fr-4m54-94mj x_refsource_CONFIRM
- https://github.com/OpenCTI-Platform/opencti/pull/14243 x_refsource_MISC
- https://github.com/OpenCTI-Platform/opencti/commit/134531ddf5ecf741006b7f0870b7c36711b96540 x_refsource_MISC
- https://github.com/OpenCTI-Platform/opencti/releases/tag/7.260326.0 x_refsource_MISC