OpenBao is an open source identity-based secrets management system. Prior to version 2.5.3, OpenBao's Certificate authentication method, when a token renewal is requested and `disable_binding=true` is set, attempts to verify the current request's presented mTLS certificate matches the original. Token renewals for other authentication methods do not require any supplied login information. Due to incorrect matching, the certificate authentication method would allow renewal of tokens for which the attacker had a sibling certificate+key signed by the same CA, but which did not necessarily match the original role or the originally supplied certificate. This implies an attacker could still authenticate to OpenBao in a similar scope, however, token renewal implies that an attacker may be able to extend the lifetime of dynamic leases held by the original token. This attack requires knowledge of either the original token or its accessor. This vulnerability is original from HashiCorp Vault. This is addressed in v2.5.3. As a workaround, ensure privileged roles are tightly scoped to single certificates.

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Tue, 21 Apr 2026 03:15:00 +0000

Type Values Removed Values Added
First Time appeared Openbao
Openbao openbao
Vendors & Products Openbao
Openbao openbao

Tue, 21 Apr 2026 01:15:00 +0000

Type Values Removed Values Added
Description OpenBao is an open source identity-based secrets management system. Prior to version 2.5.3, OpenBao's Certificate authentication method, when a token renewal is requested and `disable_binding=true` is set, attempts to verify the current request's presented mTLS certificate matches the original. Token renewals for other authentication methods do not require any supplied login information. Due to incorrect matching, the certificate authentication method would allow renewal of tokens for which the attacker had a sibling certificate+key signed by the same CA, but which did not necessarily match the original role or the originally supplied certificate. This implies an attacker could still authenticate to OpenBao in a similar scope, however, token renewal implies that an attacker may be able to extend the lifetime of dynamic leases held by the original token. This attack requires knowledge of either the original token or its accessor. This vulnerability is original from HashiCorp Vault. This is addressed in v2.5.3. As a workaround, ensure privileged roles are tightly scoped to single certificates.
Title OpenBao's Certificate Authentication Allows Token Renewal With Different Certificate
Weaknesses CWE-295
References
Metrics cvssV4_0

{'score': 2, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-21T00:43:22.920Z

Reserved: 2026-04-06T22:06:40.515Z

Link: CVE-2026-39388

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-21T01:16:06.357

Modified: 2026-04-21T01:16:06.357

Link: CVE-2026-39388

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-21T03:00:06Z

Weaknesses