CVE-2026-3089
Medium
Description
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.This issue affects prior versions of Actual Sync Server 26.3.0.
SeverityMedium
CVSS6.5
Exploit probability36. percentile0.4%
ProductActual
PublishedMar 9, 2026
First seenMar 9, 2026
Weakness typeCWE-22Path traversal
How to fix
Update
- actualbudget actual26.3.0 or later
- @actual-app/sync-server26.3.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| actualbudget actual | v < 26.3.0 | 26.3.0 |
| @actual-app/sync-servernpm | v < 26.3.0 | 26.3.0 |
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