Serendipity 2.3.5 Reflected XSS via search clean-URL route

{
  "id": "9c7cf2d37665ffa22fa964c1434051157447f3a536c277de63274209a629dc7f",
  "url": "https://osv.dev/vulnerability/CVE-2026-73628",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Serendipity 2.3.5 Reflected XSS via search clean-URL route",
    "summary": "Serendipity versions >= 2.3.5 and <= 2.6.0 contain a reflected cross-site scripting vulnerability in the search clean-URL route (/search/). In include/functions_routing.inc.php serveSearch(), the sanitisation pipeline runs urldecode() after HTML-encoding, so a single URL-encoded HTML payload survives strip_tags() and htmlspecialchars() and is then decoded back into live HTML in the page. A crafted search link can execute arbitrary JavaScript in the victim's browser. Fixed in 2.6.1.",
    "evidence": "osv:CVE-2026-73628",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-73628",
      "aliases": [
        "CVE-2026-73628",
        "GHSA-6c2x-mjmq-vx4q"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/s9y/serendipity",
              "type": "GIT",
              "events": [
                {
                  "introduced": "80676e4c9197758f5c793aa97aa86c1c088f988d"
                },
                {
                  "fixed": "9aa100a744977cd3d85e462fe5f190c866d7e8a0"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "2.3.5"
                      },
                      {
                        "last_affected": "2.6.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.6.1"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-73628.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:41.381232716Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73628.json",
        "https://github.com/s9y/Serendipity/security/advisories/GHSA-6c2x-mjmq-vx4q",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-73628",
        "https://www.vulncheck.com/advisories/serendipity-reflected-xss-via-search-clean-url-route"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73628.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-73628",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 509174,
  "published_at": "2026-08-13T11:28:26.954+00:00"
}