CVE-2026-35210OpenCTI: Authorization Bypass via `synchronized-upsert` HTTP Header Injection
- 7.1HighCVSS base score
- 0.35%Exploitation in 30 daysEPSS · top 71% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N |
| NVDNVD · Analyzed | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.35% · top 71% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.1.
Affected products
- affected < 7.260326.0
References
References4
- https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-36fr-4m54-94mj (opens in a new tab)x_refsource_CONFIRM
- https://github.com/OpenCTI-Platform/opencti/pull/14243 (opens in a new tab)x_refsource_MISC
- https://github.com/OpenCTI-Platform/opencti/commit/134531ddf5ecf741006b7f0870b7c36711b96540 (opens in a new tab)x_refsource_MISC
- https://github.com/OpenCTI-Platform/opencti/releases/tag/7.260326.0 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-42430 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-35210)Record last updated .