OpenBao is an open source identity-based secrets management system. Prior to 2.5.5, an OpenBao user with access to sys/leases/revoke/:lease_id in one namespace could revoke a lease in another namespace when the foreign lease_id was known, bypassing namespace ACL isolation. The affected lease lookup routing in vault/expiration.go allowed FetchLeaseInfo and loadEntry to resolve cached or stored lease data outside the request namespace, allowing a tenant that intentionally disclosed a lease identifier to have the lease and its underlying credential revoked by another tenant. This issue is fixed in version 2.5.5.
https://github.com/openbao/openbao/security/advisories/GHSA-c36x-h252-g9x2
https://github.com/openbao/openbao/releases/tag/v2.6.0
https://github.com/openbao/openbao/releases/tag/v2.5.5
https://github.com/openbao/openbao/pull/3310
https://github.com/openbao/openbao/pull/3307
https://github.com/openbao/openbao/commit/b20b999dd4044d7b419a5472d8fe08407828be37
https://github.com/openbao/openbao/commit/9ba1413d793223cca67db12434093a2f25fdc540
Published: 2026-09-15
Updated: 2026-09-15
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 2.1
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Low
EPSS: 0.00444