Auth bypass in Actualbudget Actual
CVE-2026-42604
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.
Vulnerability class: Broken Access Control
EPSS: 0.004 (33.5th percentile) — read the EPSS interpretation.
Affected products
- Actualbudget Actual — versions < 26.5.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_CONFIRM)