{"id":"CVE-2021-30027","aliases":["DEBIAN-CVE-2021-30027","EUVD-2021-16971","GHSA-9whf-9v4j-38v8","UBUNTU-CVE-2021-30027"],"status":"published","title":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory,...","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","severity":{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.00697,"percentile":0.53525,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-908"],"published":"2021-04-29T14:29:19Z","modified":"2026-10-23T18:03:26Z","fixes":[{"ecosystem":"Debian:12","package":"md4c","fixed_in":["0.4.7-2"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"md4c","fixed_in":["0.4.7-2"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"md4c","fixed_in":["0.4.7-2"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"md4c","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.7-2"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"md4c","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.7-2"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"md4c","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.7-2"}]}]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"md4c","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.3.4-1","0.4.1-1","0.4.2-1","0.4.3-1"]}],"products":[{"vendor":"md4c_project","product":"md4c"}],"references":[{"url":"https://github.com/mity/md4c/issues/155","tags":["x_refsource_MISC","x_transferred","Exploit","Issue Tracking","Third Party Advisory","report"]},{"url":"https://github.com/mity/md4c/commit/4fc808d8fe8d8904f8525bb4231d854f45e23a19","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-30027"},{"url":"https://github.com/advisories/GHSA-9whf-9v4j-38v8"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-30027","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-30027","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-30027","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-30027","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","status":"published","published":"2021-04-29T14:29:19Z","modified":"2024-08-03T22:24:59.154Z","updated_at":"2026-11-02T14:33:02.20241Z"}],"euvd":[{"id":"EUVD-2021-16971","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","status":"published","published":"2021-04-29T14:29:19Z","modified":"2024-08-03T22:24:59Z","updated_at":"2026-11-03T03:24:43.413555Z"}],"ghsa":[{"id":"GHSA-9whf-9v4j-38v8","title":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory,...","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","status":"published","published":"2022-05-24T17:49:06Z","modified":"2024-04-04T03:06:44Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-908"],"updated_at":"2026-11-02T14:56:13.784244Z"}],"nvd":[{"id":"CVE-2021-30027","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","status":"published","published":"2021-04-29T15:15:11.02Z","modified":"2026-06-17T03:49:36.987Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-908"],"updated_at":"2026-11-02T14:06:52.81233Z"}],"osv":[{"id":"CVE-2021-30027","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","status":"published","published":"2021-04-29T15:15:11.02Z","modified":"2026-10-20T14:24:48.506298481Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:44:19.483607Z"},{"id":"DEBIAN-CVE-2021-30027","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","status":"published","published":"2021-04-29T15:15:11.02Z","modified":"2026-10-23T18:03:26.117380376Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:45:34.94143Z"},{"id":"UBUNTU-CVE-2021-30027","description":"md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.","status":"published","published":"2021-04-29T15:15:00Z","modified":"2026-04-22T12:52:06.242691Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:54:27.332852Z"}]}}