CVE-2026-46405: Github.com/openbao/openbao OpenBao's Kerberos Auth Method Accumulates Vulnerability

MODERATE
Advisory Identifier: GHSA-7j6w-vvw2-5f9c
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CVSS 5.3
CWE-770
Published
Advisory Summary

CVE-2026-46405 is a MODERATE (CVSS 5.3) openbao's kerberos auth method accumulates vulnerability (CWE-770: Allocation of Resources Without Limits or Throttling) affecting Github.com/openbao/openbao libraries in the Go ecosystem. The issue involves openbao's kerberos auth method accumulates unaccessible tokens. Remediation is available by upgrading affected packages to version 2.5.4.

CVE-2026-46405 at a Glance

CVE Identifier CVE-2026-46405
GHSA Identifier GHSA-7j6w-vvw2-5f9c
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-770: Allocation of Resources Without Limits or Throttling
Affected Product Github.com/openbao/openbao
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability Low (A:L)

How to Fix CVE-2026-46405

To remediate this vulnerability, upgrade all affected Github.com/openbao/openbao dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/openbao/openbao fixed: 2.5.4 
Upgrade github.com/openbao/openbao to 2.5.4
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for github.com/openbao/openbao

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-46405, inspect your project dependencies for Github.com/openbao/openbao:

inspect dependencies for github.com/openbao/openbao

Analyze the terminal output to locate any version of Github.com/openbao/openbao in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.5.4), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-770: Allocation of Resources Without Limits or Throttling, where the product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. In Github.com/openbao/openbao, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact 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`. At most this could cause storage usage. ### Patches This is fixed in OpenBao v2.5.4. ### Workarounds 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. ### Reporter This was discovered by an anonymous reporter.

CVE-2026-46405 Affected Github.com/openbao/openbao Versions

1 component(s)
Fixed Versions:
2.5.4
Product / Package Ecosystem Affected Versions Fixed Version
github.com/openbao/openbao
golang/github.com/openbao/openbao
Go
< 2.5.4
2.5.4

References

GitHub Advisory / Wiki ADVISORY
https://github.com/openbao/openbao/security/advisories/GHSA-7j6w-vvw2-5f9c
Github.com/openbao/openbao Source Repository REPOSITORY
https://github.com/openbao/openbao/pull/3150
Security Fix Commit FIX COMMIT
https://github.com/openbao/openbao/commit/0d82e0a5a3b6a93e8087bcbaf0b11326c12d4f4d
Github.com/openbao/openbao Source Repository REPOSITORY
https://github.com/openbao/openbao
Github.com/openbao/openbao Release RELEASE
https://github.com/openbao/openbao/releases/tag/v2.5.4

Frequently Asked Questions

What is CVE-2026-46405?
CVE-2026-46405 is a security vulnerability in Github.com/openbao/openbao involving OpenBao's Kerberos Auth Method Accumulates Unaccessible Tokens under CWE-770: Allocation of Resources Without Limits or Throttling.
Which Github.com/openbao/openbao versions are affected?
Affected versions include releases prior to 2.5.4 across affected packages: github.com/openbao/openbao.
What version fixes CVE-2026-46405?
Upgrading to 2.5.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/openbao/openbao affected?
Yes, github.com/openbao/openbao is affected in releases prior to 2.5.4. Upgrade your dependency to 2.5.4 or later.
What is the CVSS score of CVE-2026-46405?
CVE-2026-46405 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
What CWE is associated with CVE-2026-46405?
CVE-2026-46405 is classified under CWE-770: Allocation of Resources Without Limits or Throttling (The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.).
How can I check Go dependencies for CVE-2026-46405?
Run the dependency tree command: 'inspect dependencies for github.com/openbao/openbao'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-7j6w-vvw2-5f9c",
  "modified" : "2026-05-28T18:55:23Z",
  "published" : "2026-05-28T18:55:23Z",
  "aliases" : [ "CVE-2026-46405" ],
  "summary" : "OpenBao's Kerberos Auth Method Accumulates Unaccessible Tokens",
  "details" : "### Impact\n\nIn 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`. At most this could cause storage usage.\n\n### Patches\n\nThis is fixed in OpenBao v2.5.4. \n\n### Workarounds\n\nUsers 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.\n\n### Reporter\n\nThis was discovered by an anonymous reporter.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/openbao/openbao"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.5.4"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.5.3"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/openbao/openbao/security/advisories/GHSA-7j6w-vvw2-5f9c"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openbao/openbao/pull/3150"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openbao/openbao/commit/0d82e0a5a3b6a93e8087bcbaf0b11326c12d4f4d"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/openbao/openbao"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/openbao/openbao/releases/tag/v2.5.4"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-770" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-28T18:55:23Z",
    "nvd_published_at" : null
  }
}