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—including the OAuth2 client_secret—to 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.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-863"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42604.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "26.5.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"introduced": "0"
},
{
"last_affected": "26.4.0"
}
],
"source": "DESCRIPTION"
}
]
}