CVE-2021-40407 Reolink RLC-410W IP Camera OS Command Injection Vulnerability
Reolink RLC-410W IP cameras contain an authenticated OS command injection vulnerability in the device network settings functionality.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 18 Dec 2024.
- Rated Critical severity (CVSS 9.1, scored by Vendor).
- It has been in the catalogue for 688 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
An OS command injection vulnerability exists in the device network settings functionality of reolink RLC-410W v3.0.0.136_20121102. At [1] or [2], based on DDNS type, the ddns->domain variable, that has the value of the domain parameter provided through the SetDdns API, is not validated properly. This would lead to an OS command injection. An attacker can send an HTTP request to trigger this vulnerability.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Reolink RLC-410W IP Camera. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
The impacted product could be end-of-life (EoL) and/or end-of-service (EoS). Users should discontinue product utilization if a current mitigation is unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
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