Cross-site scripting in OpenBao - CVE-2026-33758

 

Cross-site scripting in OpenBao - CVE-2026-33758

Published: April 21, 2026


Vulnerability identifier: #VU126697
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Green
CVE-ID: CVE-2026-33758
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: OpenBao
Affected software:
OpenBao

Detailed vulnerability description

The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to cross-site scripting in the OIDC authentication error message page when handling the error_description parameter for a failed authentication. A remote attacker can supply a crafted error_description parameter to disclose sensitive information.

Only installations with an OIDC/JWT authentication method enabled and a role configured with callback_mode=direct are vulnerable. User interaction is required.


How to mitigate CVE-2026-33758

Install security update from vendor's website.

Sources