Resource exhaustion in Openbao

CVE-2026-46405

OpenBao is an open source identity-based secrets management system. Prior to version 2.5.4, in OpenBao's Kerberos auth method on the `GET` handler, or when an `Authorization: Negotiate` header is supplied, the response is includes a `logical.Auth` object in addition to an error message. This results in tokens being created with only the default policy, default TTL, and no entity information, which are hidden by the returned error message. No access to these tokens by the caller occurs and the authentication token is not ever made accessible outside of `sys/raw`. This is fixed in OpenBao v2.5.4. As a workaround, users may set a rate limit quota to limit the creation of these paths. As the path is unauthenticated, it isn't possible to deny access to it.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.006 (49.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 50th percentile — 49.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-46405: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-46405?
CVE-2026-46405 is a medium-severity vulnerability in Openbao, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-08-07.
How severe is CVE-2026-46405?
Medium severity. CVSS v3 base score is 5.3 out of 10.