#VU24736 OS Command Injection in DIR-859 - CVE-2019-17621

Vulnerability identifier: #VU24736

Vulnerability risk: High

CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber]

CVE-ID: CVE-2019-17621

CWE-ID: CWE-78

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
DIR-859
Hardware solutions / Routers for home users

Vendor: D-Link

Description

The vulnerability allows a remote attacker to execute arbitrary shell commands on the target system.

The vulnerability exists due to improper input validation in the UPnP endpoint URL in /gena.cgi. A remote unauthenticated attacker can send a specially crafted HTTP SUBSCRIBE request to the UPnP service when connecting to the local network and execute arbitrary OS commands on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

DIR-859: 1.05 - 1.06b01Beta01

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External links
https://packetstormsecurity.com/files/156054/D-Link-DIR-859-Unauthenticated-Remote-Command-Execution.html
https://medium.com/@s1kr10s/d-link-dir-859-rce-unautenticated-cve-2019-17621-en-d94b47a15104
https://medium.com/@s1kr10s/d-link-dir-859-rce-unautenticated-cve-2019-17621-es-fad716629ff9
https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10146
https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10147
https://www.dlink.com/en/security-bulletin
https://www.ftc.gov/system/files/documents/cases/dlink_proposed_order_and_judgment_7-2-19.pdf

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.