How severe is CVE-2019-17621?

CVE-2019-17621 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2019-17621?

Affected package information for CVE-2019-17621 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2019-17621?

No fixed version has been published for CVE-2019-17621 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2019-17621 actively exploited in the wild?

Yes. There are 8 known exploit references for CVE-2019-17621, including 7 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2019-17621?

CVE-2019-17621 has an EPSS (Exploit Prediction Scoring System) score of 93.0%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2019-17621 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2019-17621 (D-Link DIR-859 Router Command Execution Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2023-06-29. CISA required all US federal civilian agencies to remediate this vulnerability by 2023-07-20. The required action was: Apply updates per vendor instructions or discontinue use of the product if updates are unavailable. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2019-17621?

CVE-2019-17621 is classified as OS Command Injection (CWE-78). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Which products and versions are affected by CVE-2019-17621?

CVE-2019-17621 affects dlink dir-818lx firmware; dlink dir-822 firmware; dlink dir-823 firmware (1 version, e.g. 1.00b06); dlink dir-859 firmware (1 version, e.g. 1.06b01), and 10 more product(s). Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2019-17621 published, and has it been updated?

CVE-2019-17621 was published on December 30, 2019 and was last updated on November 7, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2023-06-29 — agencies required to remediate by 2023-07-20

CVE-2019-17621

CRITICAL

The UPnP endpoint URL /gena.cgi in the D-Link DIR-859 Wi-Fi router 1.05 and 1.06B01 Beta01 allows an Unauthenticated remote attacker to execute system commands as root, by sending a…

Published

Dec 30, 2019

Updated

Nov 7, 2025

Affected

0 pkgs

Patched

None yet

Exploits

8 known

EPSS Exploitation Probability

via FIRST.org ↗

93.0%probability of exploitation in next 30 days

Very High Risk100th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

The UPnP endpoint URL /gena.cgi in the D-Link DIR-859 Wi-Fi router 1.05 and 1.06B01 Beta01 allows an Unauthenticated remote attacker to execute system commands as root, by sending a specially crafted HTTP SUBSCRIBE request to the UPnP service when connecting to the local network.

Affected Products

14 products · 21 configurations

dir-818lx firmwaredlink

all

dir-822 firmwaredlink

≤ 3.12b04

range

dir-823 firmwaredlink

≤ 1.00b06

1 version

1.00b06

dir-859 firmwaredlink

≤ 1.05b03

1 version

1.06b01

dir-865l firmwaredlink

≤ 1.07b01

range

dir-868l firmwaredlink

≤ 2.05b02

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.