SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2017-11402

Design flaws in OPC classic and in custom netfilter modules allow an attacker to remotely activate rules on the firewall and to connect to any TCP port of a protected asset, thus bypassing the firewall.

CRITICAL 9.8EPSS 1.54%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.54%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An issue has been discovered on the Belden Hirschmann Tofino Xenon Security Appliance before 03.2.00. Design flaws in OPC classic and in custom netfilter modules allow an attacker to remotely activate rules on the firewall and to connect to any TCP port of a protected asset, thus bypassing the firewall. The attack methodology is a crafted OPC dynamic port shift.

CVSS 3.0
9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.54% probability · 75th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-20
Affected
belden/tofino xenon security appliance firmware
Source
cve@mitre.org
EPSS trend
0%3%5%27 October 2026: 1.54%27 October 202627 October 2026

EPSS 1.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.