CVE-2026-21886
6.5 · MEDIUMOverview
CVE-2026-21886 is a medium-severity vulnerability affecting citeum opencti. It was published on March 17, 2026 and has a CVSS 3.1 base score of 6.5 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.5, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to version 6.9.1, the GraphQL mutations "IndividualDeletionDeleteMutation" is intended to allow users to delete individual entity objects respectively. However, it was observed that this mutation can be misused to delete unrelated and sensitive objects such as analyses reports etc. This behavior stems from the lack of validation in the API to ensure that the targeted object is contextually related to the mutation being executed. Version 6.9.1 fixes the issue.
Remediation
Check the references section for vendor advisories and patches from citeum. Update opencti to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| citeum | opencti | >= 0, < 6.9.1 | Affected |
Frequently Asked Questions
What is CVE-2026-21886?
CVE-2026-21886 is a medium-severity vulnerability affecting citeum opencti. It was published on March 17, 2026 and has a CVSS 3.1 base score of 6.5 (MEDIUM).
How severe is CVE-2026-21886?
This vulnerability has a CVSS 3.1 base score of 6.5, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-21886?
Check the references section for vendor advisories and patches from citeum. Update opencti to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-21886?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-21886 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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