Medium severity · published Aug 7, 2026
CVE-2026-46405
OpenBao's Kerberos Auth Method Accumulates Unaccessible Tokens
5.3
CVSS
0.6%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
openbao · openbao
< 2.5.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-46405
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-46405
github.com
https://github.com/openbao/openbao/commit/0d82e0a5a3b6a93e8087bcbaf0b11326c12d4f4d
github.com
https://github.com/openbao/openbao/pull/3150
github.com
https://github.com/openbao/openbao/releases/tag/v2.5.4
github.com
https://github.com/openbao/openbao/security/advisories/GHSA-7j6w-vvw2-5f9c
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