CVE-2026-27638 MEDIUM

CVE-2026-27638: ActualBudget missing authorization in sync endpoints allows cross-user budget file access in multi-user mode

Vendor Actualbudget
Product actual
Weakness CWE-862 · Missing authorization
Published February 26, 2026
Last update March 2, 2026
View on NVD All CVEs

CVSS base score

5.7/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

February 26, 2026 CVE published
March 2, 2026 Record updated