How severe is CVE-2026-27960?

CVE-2026-27960 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-27960 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27960?

CVE-2026-27960 affects Citeum Opencti. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-27960?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-27960 have an EU (EUVD) identifier?

Yes. CVE-2026-27960 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27420.

When was CVE-2026-27960 published?

CVE-2026-27960 was published on 2026-05-05 and last updated on 2026-06-17.

CVE-2026-27960

CVE-2026-27960 is a critical-severity vulnerability in Citeum Opencti with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-27420
Weakness: CWE-287
Affected product: Citeum Opencti
Published: 2026-05-05
Last modified: 2026-06-17

Description

OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. In versions 6.6.0 through 6.9.12, there is a privilege escalation vulnerability that can be exploited by unauthenticated attackers to query the API as any existing user, including the default admin account. This issue has been fixed in version 6.9.13. As a workaround, the default admin can be disabled using the `APP__ADMIN__EXTERNALLY_MANAGED` configuration.

Frequently asked questions

What is CVE-2026-27960?: OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. In versions 6.6.0 through 6.9.12, there is a privilege escalation vulnerability that can be exploited by unauthenticated attackers to query the API as any existing user, including the default admin account. This issue has been fixed in version 6.9.13. As a workaround, the default admin can be disabled using the `APP__ADMIN__EXTERNALLY_MANAGED` configuration.
How severe is CVE-2026-27960?: CVE-2026-27960 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-27960 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27960?: CVE-2026-27960 affects Citeum Opencti. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27960?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-27960 have an EU (EUVD) identifier?: Yes. CVE-2026-27960 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27420.
When was CVE-2026-27960 published?: CVE-2026-27960 was published on 2026-05-05 and last updated on 2026-06-17.

References

https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-6vvv-vmfr-xhrx

Affected products (1)

cpe:2.3:a:citeum:opencti:*:*:*:*:*:*:*:*

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