SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-3089

Actual Sync Server allows authenticated users to upload files through POST /sync/upload-user-file.

MEDIUM 5.3EPSS 0.38%

Does this matter?

Lower severity and a low EPSS score (0.38%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 4.0
5.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.38% probability · 31th percentile
CISA KEV
Not listed
Weakness
CWE-22
Affected
actualbudget/actual
Source
help@fluidattacks.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.