CVE-2026-27638

ActualBudget missing authorization in sync endpoints allows cross-user budget file access in multi-user mode

HIGH
7.1
CVSS Score
Published: February 26, 2026 at 10:14 PM UTC
Updated: June 17, 2026 at 10:27 AM UTC
1 product affected across 1 vendorActual

Using actual by actualbudget?

Get instant alerts when new vulnerabilities affect actual - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.1
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 26.2.1
Affected range stops below 26.2.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMExploitVendor Advisory
Source: cverecord
https://github.com/actualbudget/actual/security/advisories/GHSA-qmjj-p7m9-wjrv
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/actualbudget/actual/releases/tag/v26.2.1

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-862

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card