{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "3.0.0"
              },
              {
                "fixed": "10.0.13"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "DESCRIPTION"
            ]
          },
          "events": [
            {
              "introduced": "eaef3b5217226cb092d8549752831cb2a9aeaea0"
            },
            {
              "fixed": "4641de8bf0726b05851d29e66fd9e8bf423fe468"
            }
          ],
          "repo": "https://github.com/nodemailer/nodemailer",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-4ffr-jq9g-5ffx"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-1333"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/110xxx/CVE-2026-110869.json"
  },
  "details": "Nodemailer 3.0.0 before 10.0.13 has a regular expression denial of service in SMTPConnection._actionEHLO, whose four AUTH mechanism detection regexes contain overlapping whitespace sub-patterns that backtrack quadratically. A malicious or man-in-the-middle SMTP server can reply to EHLO with 250-AUTH, a long whitespace run and a non-matching token, blocking the Node.js event loop for tens of seconds to hours before authentication.",
  "id": "CVE-2026-110869",
  "modified": "2026-10-16T02:30:56.298657508Z",
  "published": "2026-10-14T22:52:57.866Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/110xxx/CVE-2026-110869.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/nodemailer/nodemailer/security/advisories/GHSA-4ffr-jq9g-5ffx"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110869"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/nodemailer-3.0.0-before-10.0.13-redos-via-smtp-auth-mechanism-detection-regexes"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Nodemailer 3.0.0 before 10.0.13 ReDoS via SMTP AUTH Mechanism Detection Regexes"
}