CVE-2021-40407
HighExploitedPublic exploitAn OS command injection vulnerability exists in the device network settings functionality of reolink RLC-410W v3.0.0.136_20121102.
Published Jan 28, 2022 · Updated Nov 3, 2025
Key Facts
Patch immediately- CVE-2021-40407 is a high-severity vulnerability (CVSS 7.2 v3.1) affecting Rlc-410w Firmware (Reolink).
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Dec 18, 2024. Public exploit code is available.
- EPSS estimates a 48% probability of exploitation in the next 30 days.
- No fixed version is listed yet; check the vendor advisory for mitigations.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
7.2
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
48%
Higher than 98.8% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
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Description
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Dec 18, 2024 | Jan 8, 2025 | Not reported |
| Industry KEV feed | Dec 18, 2024 | Jan 8, 2025 | Not reported |
| CIRCL KEV | Dec 18, 2024 | Jan 8, 2025 | Not reported |
| ENISA EUVD | Dec 18, 2024 | n/a | Not reported |
Required action: 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.
Affected Products
1 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Rlc-410w FirmwareReolink | 3.0.0.136_20121102 | n/a |
Timeline
Publicly disclosed
Jan 28, 2022
Added to CISA KEV
Dec 18, 2024
Added to Industry KEV feed
Dec 18, 2024
Added to CIRCL KEV
Dec 18, 2024
Added to ENISA EUVD
Dec 18, 2024
Last updated
Nov 3, 2025
Weakness Type
- CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
References
FAQ
Common Questions.
An OS command injection vulnerability exists in the device network settings functionality of reolink RLC-410W v3.0.0.136_20121102.
Affected: Rlc-410w Firmware (Reolink) versions 3.0.0.136_20121102. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Dec 18, 2024.
Yes. It was added on Dec 18, 2024 with a federal remediation due date of Jan 8, 2025.
Public exploit code is available.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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