{"id":"CVE-2018-20355","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-20355","generatedAt":"2026-10-28T21:19:54.621Z","title":"An invalid write of 8 bytes due to a use-after-free vulnerability in the mg_http_free_proto_data_cgi function call in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote…","description":"An invalid write of 8 bytes due to a use-after-free vulnerability in the mg_http_free_proto_data_cgi function call in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote code execution.","published":"2019-06-10T17:29:02.000Z","lastModified":"2026-06-17T01:52:41.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-416"],"affected":["cesanta/mongoose"],"epss":{"score":0.03574,"percentile":0.8931,"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":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (3.57%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/insi2304/mongoose-6.13-fuzz/blob/master/Simplest_Web_Server_Use_After_Free-mg_http_free_proto_data_cgi.png","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/insi2304/mongoose-6.13-fuzz/blob/master/Simplest_Web_Server_Use_After_Free-mg_http_free_proto_data_cgi.png","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-20355","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."}