{"id":"GHSA-wc9g-mqfw-jrwm","summary":"multer vulnerable to Denial of Service via crafted multipart field names","details":"### Impact\n\nA vulnerability in multer allows a remote, unauthenticated attacker to crash the Node.js process with a single `multipart/form-data` request. Two specially crafted text field names cause an uncaught `RangeError: Invalid array length` inside multer's field parsing, which is not routed to the application error handler and terminates the process. All applications using multer to parse multipart requests are affected.\n\n### Patches\n\nUsers should upgrade to `2.3.0`.\n\n### Workarounds\n\nNone.","aliases":["CVE-2026-77078"],"modified":"2026-09-08T21:45:04.410716306Z","published":"2026-09-08T21:30:20Z","database_specific":{"cwe_ids":["CWE-248"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-09-08T21:30:20Z","nvd_published_at":"2026-08-28T22:16:53Z"},"references":[{"type":"WEB","url":"https://github.com/expressjs/multer/security/advisories/GHSA-wc9g-mqfw-jrwm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77078"},{"type":"WEB","url":"https://github.com/expressjs/multer/commit/87a584e8c8d4da873292635fa1d8c4d78d985b76"},{"type":"WEB","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"PACKAGE","url":"https://github.com/expressjs/multer"},{"type":"WEB","url":"https://github.com/expressjs/multer/releases/tag/v2.3.0"}],"affected":[{"package":{"name":"multer","ecosystem":"npm","purl":"pkg:npm/multer"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.3.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-wc9g-mqfw-jrwm/GHSA-wc9g-mqfw-jrwm.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}