Actual has an OpenID `client_secret` Disclosure via Broken Authorization Guard in `/openid/config`_CVE-2026-42604

{
    "lastseen": "",
    "description": "Actual is a local-first personal finance tool. The `POST /openid/config` endpoint in Actual Budget's sync-server versions <= 26.4.0 exposes the full OpenID Connect configuration\u2014including the OAuth2 `client_secret`\u2014to any caller who knows the bootstrap password. The endpoint also lacks authentication and rate limiting, making the bootstrap password brute-forceable. Version 26.5.0 fixes the issue.",
    "published": "2026-06-12T18:42:38.346Z",
    "modified": "2026-06-12T18:42:38.346Z",
    "type": "cve",
    "title": "Actual has an OpenID `client_secret` Disclosure via Broken Authorization Guard in `/openid/config`",
    "source": "GitHub_M",
    "references": "https://github.com/actualbudget/actual/security/advisories/GHSA-49v6-pqjq-xw55\nhttps://actualbudget.org/blog/release-26.5.0",
    "id": "CVE-2026-42604",
    "bulletinFamily": "",
    "cwe": [
        "CWE-863"
    ],
    "cvelist": null,
    "sourceData": "actualbudget actual < 26.5.0",
    "sourceHref": "",
    "cvss": {
        "score": 6.9,
        "severity": "MEDIUM",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U",
        "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": "actual",
    "version": "< 26.5.0",
    "vendor": "actualbudget",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}