Valhalla has reflected XSS via unsanitized JSONP callback parameter

{
  "id": "b12a47b0fa22a5065581d2b3e2fc174630c59c8b3e7d800c7b89697ff9f3f37d",
  "url": "https://osv.dev/vulnerability/CVE-2026-49294",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Valhalla has reflected XSS via unsanitized JSONP callback parameter",
    "summary": "Valhalla is an open source routing engine and accompanying libraries for use with OpenStreetMap data. Versions 3.6.3 and prior are vulnerable to reflected cross-site scripting (XSS) due to improper neutralization of input in the JSONP callback parameter. When a request specifies a JSONP callback, the value is reflected directly into the HTTP response body with Content-Type: application/javascript, without any validation, output encoding, or allowlist filtering. An attacker can craft a URL containing arbitrary JavaScript in the callback parameter; if a victim is induced to load that URL via a",
    "evidence": "osv:CVE-2026-49294",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-49294",
      "aliases": [
        "CVE-2026-49294",
        "GHSA-85xx-39j8-r56x"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/valhalla/valhalla",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "e2f017b16080f49203de245a211b09efab09cf72"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "3.6.3"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "3.6.3"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "versions": [
            "3.6.3",
            "3.6.2",
            "3.6.1",
            "3.6.0",
            "3.5.1",
            "3.5.0",
            "3.4.0",
            "3.3.0",
            "3.2.1",
            "3.2.0",
            "3.1.4",
            "3.1.3",
            "3.1.2",
            "3.1.1",
            "3.1.0",
            "3.0.9",
            "3.0.8",
            "3.0.7",
            "3.0.6",
            "3.0.5",
            "3.0.4",
            "3.0.3",
            "3.0.2",
            "3.0.1",
            "3.0.0",
            "2.7.2",
            "2.7.1",
            "2.7.0",
            "2.6.1",
            "2.6.0",
            "2.5.0",
            "2.4.9",
            "2.4.8",
            "2.4.4",
            "2.4.3",
            "2.4.1",
            "2.4.0",
            "2.3.9",
            "2.3.9-rc1",
            "2.3.8",
            "2.3.7",
            "2.3.6",
            "2.3.5",
            "2.3.3",
            "2.3.4",
            "2.3.2",
            "2.3.0",
            "2.2.9",
            "2.2.8",
            "2.2.7",
            "2.2.6",
            "2.2.5",
            "2.2.4",
            "2.2.3",
            "2.2.2",
            "2.2.1",
            "2.2.0",
            "2.1.9",
            "2.1.8",
            "2.1.7",
            "2.1.6",
            "2.1.5",
            "2.1.4",
            "2.1.3",
            "2.1.2",
            "2.1.1",
            "2.1.0",
            "2.0.9",
            "2.0.8",
            "2.0.7"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49294.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:29.993314005Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49294.json",
        "https://github.com/valhalla/valhalla/security/advisories/GHSA-85xx-39j8-r56x",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-49294"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49294.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-49294",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 496693,
  "published_at": "2026-06-15T16:28:04.589+00:00"
}