{"id":"CVE-2018-18556","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-18556","generatedAt":"2026-10-28T21:19:10.712Z","title":"A privilege escalation issue was discovered in VyOS 1.1.8.","description":"A privilege escalation issue was discovered in VyOS 1.1.8. The default configuration also allows operator users to execute the pppd binary with elevated (sudo) permissions. Certain input parameters are not properly validated. A malicious operator user can run the binary with elevated permissions and leverage its improper input validation condition to spawn an attacker-controlled shell with root privileges.","published":"2018-12-17T19:29:01.000Z","lastModified":"2026-06-17T01:47:30.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":9.9,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"},"cwe":[],"affected":["vyos/vyos"],"epss":{"score":0.15411,"percentile":0.96772,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 15.4%, higher than 97% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://packetstormsecurity.com/files/159234/VyOS-restricted-shell-Escape-Privilege-Escalation.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"cve@mitre.org"},{"url":"https://blog.mirch.io/2018/11/05/cve-2018-18556-vyos-privilege-escalation-via-sudo-pppd-for-operator-users/","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://blog.vyos.io/the-operator-level-is-proved-insecure-and-will-be-removed-in-the-next-releases","tags":["Exploit","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"http://packetstormsecurity.com/files/159234/VyOS-restricted-shell-Escape-Privilege-Escalation.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://blog.mirch.io/2018/11/05/cve-2018-18556-vyos-privilege-escalation-via-sudo-pppd-for-operator-users/","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://blog.vyos.io/the-operator-level-is-proved-insecure-and-will-be-removed-in-the-next-releases","tags":["Exploit","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-18556","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."}