CVE-2026-31847

CWE-912Published: March 23, 2026· Updated: Mar 26, 2026

8.5

CVSS v3.1

EPSS:0.02%probability of exploitation in 30 daysPercentile:3.4th

Official Description

Hidden functionality in the /goform/setSysTools endpoint in Nexxt Solutions Nebula 300+ firmware through version 12.01.01.37 allows remote enablement of a Telnet service. By sending a crafted POST request with parameters such as telnetManageEn=true and telnetPwd, an authenticated attacker can activate a Telnet service on port 23. This exposes a privileged diagnostic interface that is not intended for external access and can be used to interact with the underlying system.

NVD Source

Technical Analysis

CVE-2026-31847 requires adjacent network access, limiting remote exploitation but still posing risk in shared or local network environments.

Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

CVSS v3.1 Vector Breakdown

Exploitability

Attack VectorAdjacent

Attack ComplexityLow

Privileges Req.High

User InteractionNone

ScopeX

Impact

Confidentiality

Integrity

Availability

CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X