{"id":"CVE-2021-40978","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-40978","generatedAt":"2026-11-05T01:04:12.992Z","title":"The mkdocs 1.2.2 built-in dev-server allows directory traversal using the port 8000, enabling remote exploitation to obtain :sensitive information.","description":"The mkdocs 1.2.2 built-in dev-server allows directory traversal using the port 8000, enabling remote exploitation to obtain :sensitive information. NOTE: the vendor has disputed this as described in https://github.com/mkdocs/mkdocs/issues/2601.] and https://github.com/nisdn/CVE-2021-40978/issues/1","published":"2021-10-07T14:15:08.000Z","lastModified":"2026-06-17T04:07:42.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},"cwe":["CWE-22"],"affected":["mkdocs/mkdocs"],"epss":{"score":0.15103,"percentile":0.96741,"date":"2026-11-03","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 15.1%, higher than 97% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"https://github.com/mkdocs/mkdocs","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/mkdocs/mkdocs/issues/2601","tags":["Issue Tracking","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/nisdn/CVE-2021-40978","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/nisdn/CVE-2021-40978/issues/1","tags":["Issue Tracking","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/mkdocs/mkdocs","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/mkdocs/mkdocs/issues/2601","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/nisdn/CVE-2021-40978","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/nisdn/CVE-2021-40978/issues/1","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-40978","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."}