---
title: "CVE-2026-25108: Soliton Systems K.K FileZen OS Command Injection Vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-25108/
description: "CVE-2026-25108 (Soliton Systems K.K FileZen): Exploited in the wild (CISA KEV). FileZen contains an OS command injection vulnerability. When FileZen…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-02-13
date_modified: 2026-02-26
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-25108"
kev: true
cvss: 8.7
epss: 0.05249
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-25108: Soliton Systems K.K FileZen OS Command Injection Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Soliton Systems K.K FileZen. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-02-24, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-03-17 ; treat that as the outer limit, not the target.
- EPSS 5.2% , percentile 92: FIRST’s model estimates a 5.2% chance of exploitation activity in the next 30 days, higher than 92% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.

## What it is

FileZen contains an OS command injection vulnerability. When FileZen Antivirus Check Option is enabled, a logged-in user may send a specially crafted HTTP request to execute an arbitrary OS command.

## Affected products (CVE record)

- Soliton Systems K.K. FileZen: V5.0.0 to V5.0.10
- Soliton Systems K.K. FileZen: V4.2.1 to V4.2.8

## Severity

- jpcert CVSS 3.0: 8.8 `CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`
- jpcert CVSS 4.0: 8.7 `CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: added 2026-02-24; federal due date 2026-03-17. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 5.25% probability of exploitation activity in the next 30 days; percentile 92.

## Sources

- [Listed in CISA KEV notes (jvn.jp)](https://jvn.jp/en/jp/JVN84622767/)
- [CVE.org record CVE-2026-25108](https://www.cve.org/CVERecord?id=CVE-2026-25108)
- [NVD entry CVE-2026-25108](https://nvd.nist.gov/vuln/detail/CVE-2026-25108)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-25108)
- [soliton.co.jp](https://www.soliton.co.jp/support/2026/006657.html)

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Source page: https://erroneo.us/security/cve/CVE-2026-25108/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt