OpenBao Userpass and LDAP User Lockout Bypass

Vulnerability Description

OpenBao exists to provide a software solution to manage, store, and distribute sensitive data including secrets, certificates, and keys. In versions 0.1.0 through 2.3.1, attackers could bypass the automatic user lockout mechanisms in the OpenBao Userpass or LDAP auth systems. This was caused by different aliasing between pre-flight and full login request user entity alias attributions. This is fixed in version 2.3.2. To work around this issue, existing users may apply rate-limiting quotas on the authentication endpoints:, see https://openbao.org/api-docs/system/rate-limit-quotas/.

References

• https://github.com/openbao/openbao/security/advisories/GHSA-j3xv-7fxp-gfhx
• https://github.com/openbao/openbao/commit/c52795c1ef746c7f2c510f9225aa8ccbbd44f9fc
• https://discuss.hashicorp.com/t/hcsec-2025-16-vault-userpass-and-ldap-user-lockout-bypass/76035