CVE-2026-3089

Name: CVE-2026-3089
Creator: NVD / NIST
Published: 2026-03-09T14:16:10.143+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 0.38%

Last modified Jun 17, 2026

CVE-2026-3089 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. 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.. EPSS estimates a 0.38% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

CVSS 4.0

5.3/10

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.38%

29.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

Affected Software

Vendor	Product	Versions
Actualbudget	Actual	< 26.3.0

References

https://fluidattacks.com/advisories/fugueExploit, Third Party Advisory
https://github.com/actualbudget/actualProduct
https://github.com/actualbudget/actual/pull/7067Issue Tracking, Patch
https://fluidattacks.com/advisories/fugueExploit, Third Party Advisory

Timeline

Published: Mar 9, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-3089?

How severe is CVE-2026-3089?

CVE-2026-3089 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.38% probability of exploitation in the next 30 days.

How do I fix CVE-2026-3089?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-3089?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST