Actual Sync Server's CORS proxy is intended to let authenticated users fetch resources only from repositories listed in the official plugin allowlist. When ACTUAL_GITHUB_TOKEN is configured, the proxy automatically attaches the server's GitHub token to GitHub requests. The GitHub API allowlist check uses a raw startsWith() prefix test for /repos/{owner}/{repo} without requiring a path boundary after the repository name. If an allowlisted public plugin repository is https://github.com/acme/plugin, the proxy also …
In @actual-app/sync-server, the GET /secret/:name endpoint (app-secrets.js:53) checks only that the caller has a valid session — it does not verify the caller is an admin. The sibling POST /secret/ handler does enforce an admin check in OpenID mode, exposing an authorization asymmetry. Any authenticated non-admin (BASIC) user in OpenID multi-user deployments can probe the secrets store and learn which admin-managed bank-sync integrations have been configured (existence, not values). This …
In OpenID multi-user mode, disabling a user only blocks future OpenID login for that identity. Existing Actual session tokens for the disabled user remain valid, so the user can continue calling authenticated server endpoints after an administrator has disabled the account.
Any authenticated user (including BASIC role) can escalate to ADMIN on servers migrated from password authentication to OpenID Connect. Three weaknesses combine: POST /account/change-password has no authorization check, allowing any session to overwrite the password hash; the inactive password auth row is never removed on migration; and the login endpoint accepts a client-supplied loginMethod that bypasses the server's active auth configuration. Together these allow an attacker to set a known …
Actual Sync Server allows authenticated users to upload files through POST /sync/upload-user-file. In versions prior to 26.3.0, improper validation of the user-controlled x-actual-file-id header means that traversal segments (../) can escape the intended directory and write files outside userFiles.
In multi-user mode (OpenID), the sync API endpoints (/sync/*) don't verify that the authenticated user owns or has access to the file being operated on. Any authenticated user can read, modify, and overwrite any other user's budget files by providing their file ID.
Missing authentication middleware in the ActualBudget server component allows any unauthenticated user to query the SimpleFIN and Pluggy.ai integration endpoints and read sensitive bank account balance and transaction information.