OpenBao LDAP MFA Enforcement Bypass When Using Username As Alias

Medium6.5CVE-2025-55001 · Published Aug 8, 2025 · updated Jul 27, 2026

### Impact OpenBao allows assignment of policies and MFA attribution based upon entity aliases, chosen by the underlying auth method. When using the `username_as_alias=true` parameter in the LDAP auth method, the caller-supplied username is used verbatim without normalization, allowing an attacker to bypass alias-specific MFA requirements. ### Patches OpenBao v2.3.2 will patch this issue. ### Workarounds LDAP methods are only vulnerable if using `username_as_alias=true`. Remove all usage of this parameter and update any entity aliases accordingly. ### References This issue was disclosed to HashiCorp and is the OpenBao equivalent of the following tickets: - https://discuss.hashicorp.com/t/hcsec-2025-20-vault-ldap-mfa-enforcement-bypass-when-using-username-as-alias/76092 - https://nvd.nist.gov/vuln/detail/CVE-2025-6013