Actual is a local-first personal finance tool. Prior to version 26.4.0, 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 password and authenticate as the anonymous admin account created during the multiuser migration. The three weaknesses form a single, sequential exploit chain — none produces privilege escalation on its own. Missing authorization on POST /change-password allows overwriting a password hash, but only matters if there is an orphaned row to target. Orphaned password row persisting after migration provides the target row, but is harmless without the ability to authenticate using it. Client-controlled loginMethod: "password" allows forcing password-based auth, but is useless without a known hash established by step 1. All three must be chained in sequence to achieve the impact. No single weakness independently results in privilege escalation. The single root cause is the missing authorization check on /change-password; the other two are preconditions that make it exploitable. Version 26.4.0 contains a fix.

Actual is a local-first personal finance tool. Prior to version 26.2.1, 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. Version 26.2.1 patches the issue.

Actual is a local-first personal finance tool. Prior to version 26.2.1, 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. This vulnerability allows an unauthenticated attacker to read the bank account balance and transaction history of ActualBudget users. This vulnerability impacts all ActualBudget Server users with the SimpleFIN or Pluggy.ai integrations configured. The ActualBudget Server instance must be reachable over the network. Version 26.2.1 patches the issue.