Security readout for executives and security teams
Plain-English summary
CVE-2021-40409 is a critical command injection issue in the DDNS network settings of a Reolink RLC-410W camera firmware version. A highly privileged attacker with network access to the management API could potentially make the device run unintended operating system commands.
Executive priority
Treat as urgent for environments using the named camera firmware on reachable management networks. Priority is lower where cameras are isolated and tightly administered, but remediation tracking is still warranted because device compromise could affect video confidentiality and operations.
Technical view
The issue is CWE-78 OS command injection in Reolink RLC-410W v3.0.0.136_20121102. The SetDdns API password parameter maps to ddns->password and is not properly validated for specific DDNS types, creating command execution risk. CVSS is 9.1 with network attack vector and high privileges required.
Likely exposure
Exposure appears limited to Reolink RLC-410W devices running v3.0.0.136_20121102 where authenticated high-privilege users can reach the device management interface or SetDdns API.
Exploitation context
The provided sources do not show CISA KEV listing or active exploitation. The CVSS vector indicates network reachability, low attack complexity, no user interaction, high privileges required, changed scope, and high confidentiality, integrity, and availability impact.
Researcher notes
Evidence is centered on Talos and CVE metadata. The source bundle names one firmware build but the structured affected field is n/a. Do not broaden impact beyond Reolink RLC-410W v3.0.0.136_20121102 without vendor confirmation.
Mitigation direction
- Inventory affected Reolink RLC-410W firmware versions.
- Restrict management interfaces to trusted admin networks only.
- Limit high-privilege camera accounts and rotate weak credentials.
- Check Reolink and Talos guidance for fixed firmware or workarounds.
- Disable DDNS changes where operationally unnecessary, if supported.
Validation and detection
- Confirm camera model and firmware version from asset records.
- Verify management API access is blocked from untrusted networks.
- Review DDNS settings for unexpected or unauthorized changes.
- Audit privileged camera accounts and recent administrative activity.
- Track vendor guidance for confirmed remediation status.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-78: Command execution behavior lookup
Command injection weaknesses can lead defenders to review execution techniques and command interpreter telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-40409 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.1 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H2.36Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
9.1CriticalVector: CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://talosintelligence.com/vulnerability_reports/TALOS-2021-1424CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.