CVE-2026-3089
Actual Sync Server has an Authenticated Path Traversal
EPSS 0.02%
Description
# 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`. ## Mitigations The vulnerability can be mitigated in prior versions by running the sync server in a filesystem sandbox.
How to fix CVE-2026-3089
To remediate CVE-2026-3089, upgrade the affected package to a fixed version below.
- —upgrade to 26.3.0 or later
Is CVE-2026-3089 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 26.3.0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N |