critical Known exploitedREV. 01

CVE-2019-17621D-Link DIR-859 — discovery service runs commands as root

A crafted subscribe request to the network discovery service on this D-Link router executes system commands with root privileges, and no login is involved anywhere. Firmware 1.05 and the 1.06 beta are named.

YOUR NEXT MOVE

Apply the D-Link firmware that closes this, or replace the router, and switch the network discovery service off — that service is the entry point being abused.

Read the risk

THE VITAL STATS
CVSS score
9.8/ 10
CVSS v3.1
EPSS probability
90%
Likelihood of exploitation
Attack complexity
Low
Conditions needed to exploit
Known exploited
Yes — CISA KEV
CVE published
2019-12-30
Added to KEV
2023-06-29
Exploit published
Yes
Confidence
high
Kill chain
initial access
MITRE ATT&CK
T1190
Severity
critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attacker needsNetwork access to the discovery service on the local network.

Behind the card

5 REFERENCES
Field-level provenanceTRACE THE SOURCES +

Which source supports each field, when it was retrieved, and who extracted it.

FieldsSourceRetrievedExtractorConfidence
cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_atnvd.nist.gov2026-09-24scrty-crds-pipeline/0.1high
exploitation.known_exploited, exploitation.kev_addedcisa.gov2026-09-24scrty-crds-pipeline/0.1high
epssapi.first.org2026-09-24scrty-crds-pipeline/0.1high
title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisitesnvd.nist.gov2026-09-24claude-codehigh

Printing history

THE RECORD
  1. r1Initial base card

First printing. This card has not been reprinted since publication.

crds:cve-2019-17621 · CRDS 0.1 · Issued 2026-09-24