{"id":"CVE-2021-31337","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-31337","generatedAt":"2026-10-28T00:32:01.896Z","title":"The Telnet service of the SIMATIC HMI Comfort Panels system component in affected products does not require authentication, which may allow a remote attacker to gain access to the device if the service is enabled.","description":"The Telnet service of the SIMATIC HMI Comfort Panels system component in affected products does not require authentication, which may allow a remote attacker to gain access to the device if the service is enabled. Telnet is disabled by default on the SINAMICS Medium Voltage Products (SINAMICS SL150: All versions, SINAMICS SM150: All versions, SINAMICS SM150i: All versions).","published":"2021-06-28T13:15:21.000Z","lastModified":"2026-06-17T03:51:34.000Z","status":"Modified","sourceIdentifier":"productcert@siemens.com","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-306"],"affected":["siemens/sinamics sl150 firmware","siemens/sinamics sm150 firmware","siemens/sinamics sm150i firmware"],"epss":{"score":0.01678,"percentile":0.76745,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (1.68%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://us-cert.cisa.gov/ics/advisories/icsa-21-131-04","tags":["Not Applicable","Third Party Advisory","US Government Resource"],"source":"productcert@siemens.com"},{"url":"https://us-cert.cisa.gov/ics/advisories/icsa-21-131-04","tags":["Not Applicable","Third Party Advisory","US Government Resource"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-31337","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}