CVE-2026-40946

Description

### Summary 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. ### Impact In deployments using OIDC authentication, an attacker possessing a valid JWT token issued by the same identity provider but intended for a different service (different `client_id`/`aud`) can authenticate to Oxia. This bypasses the intended audience isolation of OAuth2/OIDC. All versions using OIDC authentication are affected. ### Details In `oxiad/common/rpc/auth/oidc.go`, both `createStaticKeyVerifier()` and `createRemoteVerifier()` set `SkipClientIDCheck: true`. While a custom audience check exists in `Authenticate()`, the library-level check — which validates the `aud` claim against the expected `client_id` — is completely bypassed. ### Patches Fixed by removing `SkipClientIDCheck: true` and setting the `ClientID` field from the configured `AllowedAudiences`. ### Workarounds Ensure network-level isolation so that only trusted services can reach the Oxia gRPC endpoints.

How to fix CVE-2026-40946

To remediate CVE-2026-40946, upgrade the affected package to a fixed version below.

• —upgrade to 0.16.2 or later

Is CVE-2026-40946 being exploited?

Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.

Affected packages (1)

• from 0, < 0.16.2

CVSS scores

References (3)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2026-40946
• PATCHgithub.com/oxia-db/oxia
• WEBgithub.com/oxia-db/oxia/security/advisories/GHSA-fhvp-9hcj-6m33