{"id":"CVE-2026-31847","title":"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","summary":"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 telnetMa…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-912"],"vendor":"nexxtsolutions","product":"nebula300plus_firmware","affected":["nebula300plus_firmware <= 12.01.01.37"],"published":"2026-03-23","updated":"2026-08-10","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-31847","references":[{"url":"https://nexxt-connectivity-frontend.s3.amazonaws.com/media/docs/Nebula300+_v12.01.01.37.zip","label":"309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"},{"url":"https://www.nexxtsolutions.com/connectivity/internal-products/ARN02304U6/","label":"309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"}],"tags":["nvd"],"epss":0.00424,"epssPercentile":0.36373,"ingestedAt":"2026-08-10T12:39:46.304Z","slug":"CVE-2026-31847","body":"## Overview\n\nHidden 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.\n\n## Affected\n\n- `nebula300plus_firmware <= 12.01.01.37`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}