OpenBao has Reflected XSS in its OIDC authentication error message_CVE-2026-33758

{
    "lastseen": "",
    "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`.",
    "published": "2026-03-27T14:12:33.941Z",
    "modified": "2026-03-27T19:58:18.047Z",
    "type": "cve",
    "title": "OpenBao has Reflected XSS in its OIDC authentication error message",
    "source": "GitHub_M",
    "references": "https://github.com/openbao/openbao/security/advisories/GHSA-cpj3-3r2f-xj59\nhttps://github.com/openbao/openbao/pull/2709\nhttps://github.com/openbao/openbao/commit/6e2b2dd84f0e47cebc90d6e79609dd5274732662\nhttps://github.com/openbao/openbao/releases/tag/v2.5.2",
    "id": "CVE-2026-33758",
    "bulletinFamily": "",
    "cwe": [
        "CWE-20",
        "CWE-79",
        "CWE-116"
    ],
    "cvelist": null,
    "sourceData": "openbao openbao < 2.5.2",
    "sourceHref": "",
    "cvss": {
        "score": 9.4,
        "severity": "CRITICAL",
        "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",
        "version": "4.0"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "openbao",
    "version": "< 2.5.2",
    "vendor": "openbao",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}