{
  "schema_version": "1.4.0",
  "id": "GHSA-m697-4v8f-55qg",
  "modified": "2021-08-31T20:57:09Z",
  "published": "2021-08-05T17:04:21Z",
  "aliases": [
    "CVE-2021-32813"
  ],
  "summary": "Header dropping in traefik",
  "details": "# Impact\n\nThere exists a potential header vulnerability in Traefik's handling of the Connection header. Active exploitation of this issue is unlikely, as it requires that a removed header would lead to a privilege escalation, however, the Traefik team has addressed this issue to prevent any potential abuse.\n\n# Details\n\nIf you have a chain of Traefik middlewares, and one of them sets a request header `Important-Security-Header`, then sending a request with the following Connection header will cause it to be removed before the request was sent:\n\n```\ncurl 'https://example.com' -H \"Connection: Important-Security-Header\" -0\n```\n\nIn this case, the backend does not see the request header `Important-Security-Header`.\n\n# Patches\n\nTraefik v2.4.x: https://github.com/traefik/traefik/releases/tag/v2.4.13\n\n# Workarounds\n\nNo.\n\n# For more information\n\nIf you have any questions or comments about this advisory, [open an issue](https://github.com/traefik/traefik/issues).\n",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/traefik/traefik/v2"
      },
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.13"
            }
          ]
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/traefik/traefik"
      },
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "1.7.30"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/traefik/traefik/security/advisories/GHSA-m697-4v8f-55qg"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32813"
    },
    {
      "type": "WEB",
      "url": "https://github.com/traefik/traefik/pull/8319/commits/cbaf86a93014a969b8accf39301932c17d0d73f9"
    },
    {
      "type": "WEB",
      "url": "https://github.com/traefik/traefik/releases/tag/v2.4.13"
    },
    {
      "type": "PACKAGE",
      "url": "github.com/traefik/traefik"
    }
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-913"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2021-08-04T18:54:19Z",
    "nvd_published_at": "2021-08-03T23:15:00Z"
  }
}