OpenBao is an open source identity-based secrets management system. Prior to version 2.5.2, OpenBao installations that have an OIDC/JWT authentication method enabled and a role with `callback_mode=direct` configured are vulnerable to XSS via the `error_description` parameter on the page for a failed authentication. This allows an attacker access to the token used in the Web UI by a victim. The `error_description` parameter has been replaced with a static error message in v2.5.2. The vulnerability can be mitigated by removing any roles with `callback_mode` set to `direct`.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-cpj3-3r2f-xj59 OpenBao has Reflected XSS in its OIDC authentication error message
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 27 Mar 2026 14:30:00 +0000

Type Values Removed Values Added
Description OpenBao is an open source identity-based secrets management system. Prior to version 2.5.2, OpenBao installations that have an OIDC/JWT authentication method enabled and a role with `callback_mode=direct` configured are vulnerable to XSS via the `error_description` parameter on the page for a failed authentication. This allows an attacker access to the token used in the Web UI by a victim. The `error_description` parameter has been replaced with a static error message in v2.5.2. The vulnerability can be mitigated by removing any roles with `callback_mode` set to `direct`.
Title OpenBao has Reflected XSS in its OIDC authentication error message
Weaknesses CWE-116
CWE-20
CWE-79
References
Metrics cvssV4_0

{'score': 9.4, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-03-27T14:12:33.941Z

Reserved: 2026-03-23T18:30:14.125Z

Link: CVE-2026-33758

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-03-27T15:16:57.863

Modified: 2026-03-27T15:16:57.863

Link: CVE-2026-33758

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses