CVE-2026-31847 HIGH

CVE-2026-31847: Hidden Functionality Enables Remote Telnet Activation via /goform/setSysTools in Nexxt Nebula 300+

Vendor Nexxt Solutions
Product Nebula 300+
Weakness CWE-912
Published March 23, 2026
Last update August 10, 2026
View on NVD All CVEs

CVSS base score

8.5/10
Attack vector Adjacent
Attack complexity Low
Privileges required High
User interaction None
Confidentiality —
Integrity —

CVSS vector

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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

March 23, 2026 CVE published
August 10, 2026 Record updated