CVE-2021-45382
RCE in Dlink Dir-820L Firmware
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2021-45382 is a critical-severity OS Command Injection (CWE-78) vulnerability in Dlink Dir-820L Firmware. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique NTDS (T1003.003); ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
A remote command execution vulnerability exists in the DDNS function of the ncc2 binary on D-Link DIR-810L, DIR-820L/LW, DIR-826L, DIR-830L, and DIR-836L routers across all hardware revisions. The flaw is tracked as CVE-2021-45382, carries a CVSS 3.1 score of 9.8, and is categorized under CWE-78 for improper neutralization of special elements used in an OS command.
An unauthenticated attacker with network access can send crafted requests to the affected DDNS component and execute arbitrary commands on the device, resulting in full compromise of confidentiality, integrity, and availability without any user interaction.
D-Link has stated in advisory SAP10264 that all listed models have reached end-of-life and end-of-service status, so no firmware patches will be issued. The vulnerability is also catalogued by CISA as actively exploited in the wild, with public proof-of-concept code available.
The GitHub repository linked in the references demonstrates command injection via the DDNS interface on unpatched units.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-32155
Vulnerability Data
A Remote Command Execution (RCE) vulnerability exists in all series H/W revisions D-link DIR-810L, DIR-820L/LW, DIR-826L, DIR-830L, and DIR-836L routers via the DDNS function in ncc2 binary file. Note: DIR-810L, DIR-820L, DIR-830L, DIR-826L, DIR-836L, all hardware revisions, have reached their…
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End of Life ("EOL") /End of Service Life ("EOS") Life-Cycle and as such this issue will not be patched.
- CWE(s)
- KEV Date Added
- 04 April 2022
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.2.5V1.2.8
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.
Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.