{"id":"CVE-2021-42740","aliases":["GHSA-g4rg-993r-mgx7"],"url":"https://o3.security/vulnerability/CVE-2021-42740","summary":"Improper Neutralization of Special Elements used in a Command in Shell-quote","details":"The shell-quote package before 1.7.3 for Node.js allows command injection. An attacker can inject unescaped shell metacharacters through a regex designed to support Windows drive letters. If the output of this package is passed to a real shell as a quoted argument to a command with exec(), an attacker can inject arbitrary commands. This is because the Windows drive letter regex character class is {A-z] instead of the correct {A-Za-z]. Several shell metacharacters exist in the space between capital letter Z and lower case letter a, such as the backtick character.","published":"2021-10-21T15:15:07.633Z","modified":"2026-08-28T14:32:46.129142Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"shell-quote","fixedVersion":"1.7.3"}],"fix":{"url":"https://github.com/substack/node-shell-quote/commit/5799416ed454aa4ec9afafc895b4e31760ea1abe","label":"substack/node-shell-quote@5799416"},"references":[{"type":"ADVISORY","url":"https://github.com/substack/node-shell-quote/blob/master/CHANGELOG.md#173"},{"type":"ADVISORY","url":"https://www.npmjs.com/package/shell-quote"},{"type":"FIX","url":"https://github.com/substack/node-shell-quote/commit/5799416ed454aa4ec9afafc895b4e31760ea1abe"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-42740"},{"type":"WEB","url":"https://github.com/ljharb/shell-quote/commit/5799416ed454aa4ec9afafc895b4e31760ea1abe"},{"type":"PACKAGE","url":"https://github.com/ljharb/shell-quote"},{"type":"WEB","url":"https://github.com/ljharb/shell-quote/blob/master/CHANGELOG.md#173"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-28T14:32:46.129142Z"}}