{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "6.28.0"
              },
              {
                "introduced": "7.0.0"
              },
              {
                "fixed": "7.29.0"
              },
              {
                "introduced": "8.0.0"
              },
              {
                "fixed": "8.9.0"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "01a912e49a50c48009ed2639d2a457a6ec26752a"
            },
            {
              "introduced": "1cfe0949053aac6267f11b919cee9315a27f1fd6"
            },
            {
              "fixed": "9e38fc121d2eb26086d41c7d9379b47a6fada1c5"
            },
            {
              "introduced": "d7fbba51772deecb830a297647456a5e9f9fec57"
            },
            {
              "fixed": "21a8e1ed1843e74c3004a2926c12bb0ceaca6b71"
            }
          ],
          "repo": "https://github.com/nodejs/undici",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-v3r7-h72x-cjcm"
  ],
  "database_specific": {
    "cna_assigner": "openjs",
    "cwe_ids": [
      "CWE-74"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16729.json"
  },
  "details": "undici's setCookie function does not fully sanitize cookie attributes. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a domain value is not checked for semicolons and entries in the unparsed array are not sanitized, so attacker-influenced input can inject additional cookie attributes. For example, a domain value containing a semicolon can append attributes such as SameSite, and an unparsed entry can inject attributes such as HttpOnly, without the caller setting them. Applications that pass user-controlled input to these fields, such as multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, or the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.",
  "id": "CVE-2026-16729",
  "modified": "2026-08-01T03:33:00.477039601Z",
  "published": "2026-07-29T16:45:57.001Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://cna.openjsf.org/security-advisories.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16729.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/nodejs/undici/security/advisories/GHSA-v3r7-h72x-cjcm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-16729"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields"
}