# CVE-2026-126310: OpenBao before 2.6.5 and 2.7.2 OIDC Provider Authentication Bypass via Client Credentials

Status: published. Published: 2026-11-13. Updated: 2026-11-13.

OpenBao before 2.6.5 and 2.7.2 contains an authentication bypass vulnerability that allows unauthenticated callers to obtain OIDC ID tokens by abusing public clients with client_credentials enabled. Attackers who know a public client's client_id can request tokens from the identity/oidc/provider/<name>/token endpoint to impersonate the client without any secret.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- openbao / openbao (github.com/openbao/openbao/v2): ≥ 0; < 2.6.5 (affected, semver); 2.6.5 (unaffected, semver); ≥ 2.7.0; < 2.7.2 (affected, semver); 2.7.2 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 7 (high); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 8.7 (high); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N; source: CNA: VulnCheck

- CVSS 4.0: 7 (high); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 8.7 (high); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-287

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/openbao/openbao/security/advisories/GHSA-q824-44ff-f5j5 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/openbao-before-2.6.5-and-2.7.2-oidc-provider-authentication-bypass-via-client-credentials (CNA: VulnCheck; third-party-advisory)

- https://github.com/openbao/openbao/security/advisories/GHSA-q824-44ff-f5j5 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/openbao-before-2.6.5-and-2.7.2-oidc-provider-authentication-bypass-via-client-credentials (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-126310; retrieved 2026-11-13; source updated 2026-11-13

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-126310; retrieved 2026-11-13; source updated 2026-11-13

Revision: e4e4a70baf885b32503a84c5398f77a713597d153fede5909b7a6b0ff9839c4b

Canonical: https://y2.dev/cve/CVE-2026-126310

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