---
title: "CVE-2026-106931: EG Secure Solutions SiteGuard Server Edition OS Command Injection Vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-106931/
description: "CVE-2026-106931 (EG Secure Solutions SiteGuard Server Edition): Exploited in the wild (CISA KEV). SiteGuard Server Edition contains an OS command injection…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-10-14
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-106931"
kev: true
cvss: 8.5
epss: 0.01367
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-106931: EG Secure Solutions SiteGuard Server Edition 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 EG Secure Solutions SiteGuard Server Edition. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-10-20, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-10-23 ; treat that as the outer limit, not the target.
- EPSS 1.4% , percentile 72: FIRST’s model estimates a 1.4% chance of exploitation activity in the next 30 days, higher than 72% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Needs local access needed. Lower urgency for most teams unless an attacker could already run code on the machine.
- Editorial verdict: Patch this week. SiteGuard WAF CVE-2026-106931: Exploited Command Injection — If you run SiteGuard Server Edition, save its diagnostic data and patch this week, sooner on public web servers; the bug is exploited, but its local rating means attackers need a foothold first.

## What it is

SiteGuard Server Edition contains an OS command injection vulnerability, which may allow an attacker to execute arbitrary OS commands with root or SYSTEM privileges on the system running the affected product.

## Affected products (CVE record)

- EG Secure Solutions Inc. SiteGuard Server Edition for Apache httpd: Ver2.20 < Ver8.00 Update 5
- EG Secure Solutions Inc. SiteGuard Server Edition for Nginx: Ver2.20 < Ver8.00 Update 5
- EG Secure Solutions Inc. SiteGuard Server Edition for IIS: Ver2.20 < Ver8.00 Update 5
- EG Secure Solutions Inc. SiteGuard Server Edition for Apache httpd on FreeBSD: Ver2.20 < Ver7.00 Update 6
- EG Secure Solutions Inc. SiteGuard Server Edition for Nginx on FreeBSD: Ver2.20 < Ver7.00 Update 6

## Severity

- jpcert CVSS 3.0: 7.8 `CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`
- jpcert CVSS 4.0: 8.5 `CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: added 2026-10-20; federal due date 2026-10-23. Known ransomware use: Unknown.
- CISA required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 1.37% probability of exploitation activity in the next 30 days; percentile 72.

## Sources

- [Listed in CISA KEV notes (eg-secure.co.jp)](https://www.eg-secure.co.jp/siteguard/news/alert-202610-1)
- [CVE.org record CVE-2026-106931](https://www.cve.org/CVERecord?id=CVE-2026-106931)
- [NVD entry CVE-2026-106931](https://nvd.nist.gov/vuln/detail/CVE-2026-106931)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-106931)
- [Listed in CISA KEV notes (cisa.gov)](https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk)
- [Listed in CISA KEV notes (cisa.gov)](https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk)
- [jvn.jp](https://jvn.jp/en/jp/JVN88474777/)

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Source page: https://erroneo.us/security/cve/CVE-2026-106931/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt