CVE-2025-54999 is a low-severity (CVSS 3.7) CWE-203 vulnerability in github.com/openbao/openbao. A fix is available for github.com/openbao/openbao — see the affected versions and patch details below.
OpenBao: Timing Side-Channel in Userpass Auth Method
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-54999.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2025-54999 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/openbao/openbao🐹github.com/openbao/openbaoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Impact
When using OpenBao's userpass auth method, user enumeration was possible due to timing difference between non-existent users and users with stored credentials. This is independent of whether the supplied credentials were valid for the given user.
Patches
OpenBao v2.3.2 will patch this issue.
Workarounds
Users may use another auth method or apply rate limiting quotas to limit the number of requests in a period of time: 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-2025-15-timing-side-channel-in-vault-s-userpass-auth-method/76034
- https://nvd.nist.gov/vuln/detail/CVE-2025-6011
Barring further information, this is also assumed to cover and remediate the following additional vulnerability:
- https://discuss.hashicorp.com/t/hcsec-2025-21-vault-user-enumeration-in-userpass-auth-method/76095
- https://nvd.nist.gov/vuln/detail/CVE-2025-6010
If this is not the case as further details emerge, a new CVE will be assigned for remediating that. Otherwise, no further CVE will be sought.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/openbao/openbao | ≥ 0.1.0&&< 2.3.2 | 2.3.2go get github.com/openbao/openbao@v2.3.2 |
| 🐹Go | github.com/openbao/openbao | all versions | 0.0.0-20250806193356-4d9b5d3d6486go get github.com/openbao/openbao@v0.0.0-20250806193356-4d9b5d3d6486 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/openbao/openbao, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/openbao/openbao to 2.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-54999 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-54999 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-54999. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-54999 in your dependencies?
O3 Security finds CVE-2025-54999 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.