#VU21162 Integer underflow in CUJO Smart Firewall

Published: 2019-09-17

Vulnerability identifier: #VU21162

Vulnerability risk: High

CVSSv3.1: 8.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H/E:P/RL:U/RC:C]

CVE-ID: CVE-2018-4011


Exploitation vector: Network

Exploit availability: No

Vulnerable software:
CUJO Smart Firewall
Client/Desktop applications / Antivirus software/Personal firewalls

Vendor: CUJO AI


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

The vulnerability exists because of integer underflow in the "mdnscap" binary when parsing SRV records in an mDNS packet due to the "RDLENGTH" value is handled incorrectly. A remote attacker can send a specially crafted mDNS message to the affected application, trigger integer underflow and execute arbitrary code on the target system.

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

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

CUJO Smart Firewall: 7003

External links

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?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

Latest bulletins with this vulnerability