How severe is CVE-2026-40946?

CVE-2026-40946 has a CVSS 4.0 base score of 9.2, rated critical severity.

Is CVE-2026-40946 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40946?

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-2026-40946 have an EU (EUVD) identifier?

Yes. CVE-2026-40946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24512.

When was CVE-2026-40946 published?

CVE-2026-40946 was published on 2026-04-21 and last updated on 2026-06-17.

CVE-2026-40946

CVE-2026-40946 is a critical-severity vulnerability with a CVSS 4.0 base score of 9.2. 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 4.0 base score 9.2)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-24512
Weakness: CWE-287
Published: 2026-04-21
Last modified: 2026-06-17

Description

Oxia is a metadata store and coordination system. Prior to 0.16.2, the OIDC authentication provider unconditionally sets SkipClientIDCheck: true in the go-oidc verifier configuration, disabling the standard audience (aud) claim validation at the library level. This allows tokens issued for unrelated services by the same OIDC issuer to be accepted by Oxia. This vulnerability is fixed in 0.16.2.

Frequently asked questions

What is CVE-2026-40946?: Oxia is a metadata store and coordination system. Prior to 0.16.2, the OIDC authentication provider unconditionally sets SkipClientIDCheck: true in the go-oidc verifier configuration, disabling the standard audience (aud) claim validation at the library level. This allows tokens issued for unrelated services by the same OIDC issuer to be accepted by Oxia. This vulnerability is fixed in 0.16.2.
How severe is CVE-2026-40946?: CVE-2026-40946 has a CVSS 4.0 base score of 9.2, rated critical severity.
Is CVE-2026-40946 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-40946?: 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-2026-40946 have an EU (EUVD) identifier?: Yes. CVE-2026-40946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24512.
When was CVE-2026-40946 published?: CVE-2026-40946 was published on 2026-04-21 and last updated on 2026-06-17.

References

https://github.com/oxia-db/oxia/security/advisories/GHSA-fhvp-9hcj-6m33

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