---
title: "CVE-2021-36380: Sunhillo SureLine OS Command Injection Vulnerablity"
url: https://erroneo.us/security/cve/CVE-2021-36380/
description: "CVE-2021-36380 (Sunhillo SureLine): Exploited in the wild (CISA KEV). Sunhillo SureLine before 8.7.0.1.1 allows Unauthenticated OS Command Injection via…"
type: vulnerability-record
section: "Security Digest"
date_published: 2021-08-13
date_modified: 2025-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2021-36380"
kev: true
cvss: 9.8
epss: 0.97832
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2021-36380: Sunhillo SureLine OS Command Injection Vulnerablity

**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 Sunhillo SureLine. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2024-03-05, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2024-03-26 ; treat that as the outer limit, not the target.
- EPSS 97.8% , percentile 99.9: FIRST’s model estimates a 97.8% chance of exploitation activity in the next 30 days, higher than 99.9% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.

## What it is

Sunhillo SureLine before 8.7.0.1.1 allows Unauthenticated OS Command Injection via shell metacharacters in ipAddr or dnsAddr /cgi/networkDiag.cgi.

## Affected products (CVE record)

- n/a n/a: see advisory

## Severity

- CISA-ADP CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: added 2024-03-05; federal due date 2024-03-26. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 97.83% probability of exploitation activity in the next 30 days; percentile 99.9.

## Sources

- [Listed in CISA KEV notes (sunhillo.com)](https://www.sunhillo.com/fb011/)
- [CVE.org record CVE-2021-36380](https://www.cve.org/CVERecord?id=CVE-2021-36380)
- [NVD entry CVE-2021-36380](https://nvd.nist.gov/vuln/detail/CVE-2021-36380)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36380)
- [sunhillo.com](https://www.sunhillo.com/product/sureline/)
- [research.nccgroup.com](https://research.nccgroup.com/2021/07/26/technical-advisory-sunhillo-sureline-unauthenticated-os-command-injection-cve-2021-36380/)

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Source page: https://erroneo.us/security/cve/CVE-2021-36380/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt