CVE-2026-33758
EPSS 0.05%OpenBao has Reflected XSS in its OIDC authentication error message
Published: 3/26/2026Modified: 3/27/2026
Description
### Impact 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. ### Patches The `error_description` parameter has been replaced with a static error message in v2.5.2 ### Workarounds The vulnerability can be mitigated by removing any roles with `callback_mode` set to `direct`.
Affected packages (2)
- Go/github.com/openbao/openbaofrom 0, < 0.0.0-20260325133417-6e2b2dd84f0e
- Go/github.com/openbao/openbaofrom 0, < 0.0.0-20260325133417-6e2b2dd84f0e
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | 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 |
References (6)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-33758
- PATCHhttps://github.com/openbao/openbao
- WEBhttps://github.com/openbao/openbao/commit/6e2b2dd84f0e47cebc90d6e79609dd5274732662
- WEBhttps://github.com/openbao/openbao/pull/2709
- WEBhttps://github.com/openbao/openbao/releases/tag/v2.5.2
- WEBhttps://github.com/openbao/openbao/security/advisories/GHSA-cpj3-3r2f-xj59