CVE-2021-45382 — Doudoudedi
CRITICALCVE-2021-45382 is a critical-severity (CVSS 9.8) OS Command Injection vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2022-04-04) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.
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…
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2022-04-04. Federal agencies were required to remediate by 2022-04-25.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2021-45382.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-45382 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Counts from FIRST.org, log-scaled.
Description
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 End of Life ("EOL") /End of Service Life ("EOS") Life-Cycle and as such this issue will not be patched.
Affected Products
dir-810l firmwaredlinkdir-820l firmwaredlinkdir-820lw firmwaredlinkdir-826l firmwaredlinkdir-830l firmwaredlinkdir-836l firmwaredlinkResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
VulnerabilityDetect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
No fixed release is recorded for CVE-2021-45382 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.
How to detect CVE-2021-45382
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2021-45382 -u https://target- Template
- D-Link - Remote Command Execution
- Severity
- critical
- Impact
- Unauthenticated attackers can execute arbitrary system commands via command injection in the DDNS function, leading to complete router compromise and control over network traffic.
- Remediation
- DIR-810L, DIR-820L, DIR-830L, DIR-826L, DIR-836L, all hardware revisions, have reached their End of Life ("EOL") /End of Service Life ("EOS") Life-Cycle and as such this issue will not be patched.
Template by ProjectDiscovery nuclei-templates (king-alexander), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2021-45382 in your dependencies?
Find it across , including transitive dependencies.