PatchTheCVECVE-2021-36380: Sunhillo SureLine OS Command Injection Vulnerablity
CVE-2021-36380 is a critical-severity flaw (CVSS 9.8) affecting sureline, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Sunhillo SureLine before 8.7.0.1.1 allows Unauthenticated OS Command Injection via shell metacharacters in ipAddr or dnsAddr /cgi/networkDiag.cgi.
Why this priority
- Critical severity
- EPSS top 1%: very likely to be exploited
- Exploited in the wild (CISA KEV)
- Public exploit reference
- CISA SSVC: automatable with total technical impact
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 97.8% (top 1%) |
| CISA exploited list | Yes, fix due 2024-03-26 |
| Weakness | CWE-78 |
| Published | 2021-08-13 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Exploited Added to the CISA Known Exploited Vulnerabilities list
- Deadline CISA due date for US federal agencies to patch
- Updated Record last modified
Exact fixes by distribution
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- Write-up: research.nccgroup.com/2021/07/26/technical-advisory-sunhillo-sureline-unauthenticated-os-c
- Nuclei scan template: Sunhillo SureLine <8.7.0.1.1 - Unauthenticated OS Command Injection
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2021-36380?
sureline: upgrade to 8.7.0.1.1. Exact commands for each OS are on this page.
Is CVE-2021-36380 being exploited?
Yes. CVE-2021-36380 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.
What does CVE-2021-36380 affect?
CVE-2021-36380 affects sureline. Severity is critical (CVSS 9.8). Sunhillo SureLine before 8.7.0.1.1 allows Unauthenticated OS Command Injection via shell metacharacters in ipAddr or dnsAddr /cgi/networkDiag.cgi.
How urgent is CVE-2021-36380?
Priority 97/100. Critical severity; EPSS top 1%: very likely to be exploited; Exploited in the wild (CISA KEV); Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action