CVE-2026-33318

Technical Description

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,

Remediation

Check the references section for vendor advisories and patches from actualbudget. Update actual to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

References