OpenBao Login MFA Bypass of Rate Limiting and TOTP Token Reuse

CVE-2025-55003 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

Impact

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.

Patches

OpenBao v2.3.2 will patch this issue.

Workarounds

Use of rate-limiting quotas can limit an attacker's ability to exploit this: https://openbao.org/api-docs/system/rate-limit-quotas/

References

This issue was disclosed to HashiCorp and is the OpenBao equivalent of the following tickets:

  • https://discuss.hashicorp.com/t/hcsec-2025-19-vault-login-mfa-bypass-of-rate-limiting-and-totp-token-reuse/76038
  • https://nvd.nist.gov/vuln/detail/CVE-2025-6015

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-08-08 14:44:49 UTC
Updated
2025-08-11 13:56:55 UTC
GitHub reviewed
2025-08-08 14:44:49 UTC
NVD published
2025-08-08

EPSS Score

Score Percentile
0.04% 11.62%

CVSS Scores

Base score Version Severity Vector
5.7 3.1 —
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

Type Value
GHSA GHSA-rxp7-9q75-vj3p ↗
CVE CVE-2025-55003 ↗

CWEs

CWE id Name
CWE-307 Improper Restriction of Excessive Authentication Attempts

Affected packages (2)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
go github.com/openbao/openbao >= 0.1.0, < 2.3.2 2.3.2 —
go github.com/openbao/openbao < 0.0.0-20250807113757-8340a6918f6c 0.0.0-20250807113757-8340a6918f6c —

References

cvelogic Threat Intelligence