OpenBao has Reflected XSS in its OIDC authentication error message
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.4epss 0.3%
exploitation probability
0.3%top 79% of all CVEs
observed exploitation
nono source reports it
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`.
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
Affected products
openbao · openbaoReferences
https://access.redhat.com/security/cve/CVE-2026-33758https://bugzilla.redhat.com/show_bug.cgi?id=2452294https://github.com/openbao/openbao/commit/6e2b2dd84f0e47cebc90d6e79609dd5274732662https://github.com/openbao/openbao/pull/2709https://github.com/openbao/openbao/releases/tag/v2.5.2https://github.com/openbao/openbao/security/advisories/GHSA-cpj3-3r2f-xj59https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33758.json