Multer vulnerable to Denial of Service via incomplete cleanup

{
  "id": "abb9c78d72f819cdc8945cd79ace1b5815c87409bec16173b23be8d249c9ad55",
  "url": "https://osv.dev/vulnerability/CVE-2026-3304",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Multer vulnerable to Denial of Service via incomplete cleanup",
    "summary": "Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.0 allows an attacker to trigger a Denial of Service (DoS) by sending malformed requests, potentially causing resource exhaustion. Users should upgrade to version 2.1.0 to receive a patch. No known workarounds are available.",
    "evidence": "osv:CVE-2026-3304",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-3304",
      "aliases": [
        "CVE-2026-3304",
        "GHSA-xf7r-hgr6-v32p"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/expressjs/multer",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "809f9ddac298a5aff4686e14cfac8d003b93e9c9"
                },
                {
                  "fixed": "739919097dde3921ec31b930e4b9025036fa74ee"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:expressjs:multer:*:*:*:*:*:node.js:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.1.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "739919097dde3921ec31b930e4b9025036fa74ee"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.0.2",
            "v2.0.1",
            "v2.0.0",
            "v1.4.5-lts.2",
            "v1.4.5-lts.1",
            "v1.4.4",
            "v1.4.4-lts.1",
            "v1.4.3",
            "v1.4.2",
            "v1.4.1",
            "v1.4.0",
            "v1.3.1",
            "v1.3.0",
            "v1.2.1",
            "v1.2.0",
            "v1.1.0",
            "v1.0.6",
            "v1.0.5",
            "v1.0.4",
            "v1.0.3",
            "v1.0.2",
            "v1.0.1",
            "v1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-3304.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:31.019023751Z",
      "provider": "osv",
      "references": [
        "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3304.json",
        "https://www.cve.org/CVERecord?id=CVE-2026-3304",
        "https://access.redhat.com/errata/RHSA-2026:6174",
        "https://access.redhat.com/errata/RHSA-2026:6802",
        "https://access.redhat.com/security/cve/CVE-2026-3304",
        "https://cna.openjsf.org/security-advisories.html",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/3xxx/CVE-2026-3304.json",
        "https://github.com/expressjs/multer/security/advisories/GHSA-xf7r-hgr6-v32p",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-3304",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2443353",
        "https://github.com/expressjs/multer/commit/739919097dde3921ec31b930e4b9025036fa74ee"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-459"
        ],
        "cna_assigner": "openjs",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/3xxx/CVE-2026-3304.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-3304",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 497957,
  "published_at": "2026-02-27T15:44:37.187+00:00"
}