CVE-2026-46405 OpenBao's Kerberos Auth Method Accumulates Unaccessible Tokens
Unauthenticated requests to OpenBao's Kerberos auth method create hidden tokens, potentially exhausting resources and causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-46405?
CVE-2026-46405 is a medium-severity denial of service vulnerability in openbao, published on 7 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-770
Which versions are affected by CVE-2026-46405?
4 open source packages ship an affected version, including github.com/openbao/openbao and openbao.
| Package | Affected | Fixed in |
|---|---|---|
github.com/openbao/openbao Go | All versions | None |
github.com/openbao/openbao Go | All versions | 2.5.4 |
github.com/openbao/openbao Go | All versions | 2.5.4 |
openbao Bitnami | All versions | 2.5.4 |
How do I fix CVE-2026-46405?
Upgrade github.com/openbao/openbao to 2.5.4 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-46405 being exploited?
There is no known exploitation of CVE-2026-46405 in the wild and no public exploit code.
Sources
Also known as BIT-openbao-2026-46405, GHSA-7j6w-vvw2-5f9c, GO-2026-5225.