CVE-2025-55003mediumCWE-307

CVE-2025-55003: medium-severity vulnerability in openbao

OpenBao Login MFA Bypasses Rate Limiting and TOTP Token Reuse

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.7epss 0.3%
In short

OpenBao's MFA system accepts TOTP codes with whitespace characters, allowing attackers to bypass rate limiting and reuse old codes to gain unauthorized access. This vulnerability affects versions 2.3.1 and below.

Technical detail

CWE-307 flaw in OpenBao 2.3.1 and earlier where TOTP token normalization accepts whitespace-padded codes, bypassing internal rate-limiting checks and enabling token reuse attacks. Exploitation requires network access to the login endpoint and a valid or previously captured TOTP code, potentially leading to unauthorized authentication.

Summary generated and translated by AI from the official description.
OpenBao exists to provide a software solution to manage, store, and distribute sensitive data including secrets, certificates, and keys. In versions 2.3.1 and below, 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. This issue was fixed in version 2.3.2. To work around this, use of rate-limiting quotas can limit an attacker's ability to exploit this: https://openbao.org/api-docs/system/rate-limit-quotas/.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N
Affected products
openbao · openbao
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