{"action":"Upgrade mkdocs to 1.2.3 or later.","affected":[{"fixed":"1.2.3","introduced":"1.2.2"}],"component":"mkdocs","cve_ids":["CVE-2021-40978"],"ecosystem":"PyPI","epss":0.15103,"exploited":false,"fixed_versions":["1.2.3"],"ghsa_id":"GHSA-qh9q-34h6-hcv9","id":"tcs_01M5KGFS9A4WW3RV9N72WBDHRM","modified_at":"2026-06-10T17:02:16.308115975Z","published_at":"2021-10-07T14:15:00Z","references":["https://osv.dev/vulnerability/PYSEC-2021-878","https://github.com/nisdn/CVE-2021-40978","https://github.com/mkdocs/mkdocs","https://github.com/nisdn/CVE-2021-40978/issues/1","https://github.com/mkdocs/mkdocs/issues/2601","https://github.com/advisories/GHSA-qh9q-34h6-hcv9"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"PYSEC-2021-878","url":"https://osv.dev/vulnerability/PYSEC-2021-878"}],"summary":"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 h"}