OpenBao's Login Multi-Factor Authentication (MFA) system allows enforcing MFA using Time-based One Time Password (TOTP). Due to normalization applied by the underlying TOTP library, codes were accepted which could contain whitespace; this whitespace could bypass internal rate limiting of the MFA method and allow reuse of existing MFA codes.
OpenBao v2.3.2 will patch this issue.
Use of rate-limiting quotas can limit an attacker's ability to exploit this: https://openbao.org/api-docs/system/rate-limit-quotas/
This issue was disclosed to HashiCorp and is the OpenBao equivalent of the following tickets:
{
"severity": "MODERATE",
"github_reviewed": true,
"nvd_published_at": "2025-08-09T03:15:47Z",
"cwe_ids": [
"CWE-307"
],
"github_reviewed_at": "2025-08-08T14:44:49Z"
}