Detections
Analytics

LOYTEC L-IP BACnet/IP Routers Unchecked Input for Loop Condition (CVE-2026-55731)

high Tenable OT Security Plugin ID 505947

Synopsis

The remote OT asset is affected by a vulnerability.

Description

The SNMP agent of a LOYTEC L-IP BACnet/IP router does not bound the loop condition it derives from an SNMP GETNEXT request's OID. An unauthenticated remote attacker can send a crafted GETNEXT request containing an oversized OID component to drive the agent into a long-running loop, exhausting CPU resources and causing a persistent denial of service.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Upgrade to firmware version 8.4.18 or later.

See Also

http://www.nessus.org/u?7aec66ed

Plugin Details

Severity: High

ID: 505947

File Name: tenable_ot_loytecelectronics_CVE-2026-55731.nasl

Version: 1.1

Type: Remote

Family: Tenable.ot

Published: 9/7/2026

Updated: 9/7/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.75

CVSS v3

Risk Factor: High

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS v4

Risk Factor: High

Base Score: 8.7

Threat Score: 6.6

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Vulnerability Information

CPE: cpe:/o:loytec:lip-me201c_firmware, cpe:/o:loytec:lip-me202c_firmware, cpe:/o:loytec:lip-me204c_firmware

Required KB Items: Tenable.ot/LOYTECElectronics

Exploit Ease: No known exploits are available

Patch Publication Date: 7/3/2026

Vulnerability Publication Date: 7/3/2026

Reference Information

CVE: CVE-2026-55731

CWE: 606