Guardian Language-System XSS via id Parameter in media.php

{
  "id": "f75b321a40bc19341fbf1d2f41f2d2e75dbf6262ffc37c33fb20f96d8bc0485e",
  "url": "https://osv.dev/vulnerability/CVE-2026-34098",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Guardian Language-System XSS via id Parameter in media.php",
    "summary": "Guardian language-system fails to sanitize the id GET parameter before inserting it into HTML source and form action attributes in media.php (lines 119, 129). An authenticated attacker can craft a URL that injects script tags executing in the victim's browser session.",
    "evidence": "osv:CVE-2026-34098",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-34098",
      "aliases": [
        "CVE-2026-34098"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/guardian/language-system",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "e42c395ec4b03fe62973a669c9209a673838b8a4"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "e42c395ec4b03fe62973a669c9209a673838b8a4"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-34098.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:31.199774956Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34098.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-34098",
        "https://www.vulncheck.com/advisories/guardian-language-system-xss-via-id-parameter-in-media-php",
        "https://github.com/guardian/language-system",
        "https://gist.github.com/cyberinforepo/d5b2771d82e1b31b8fc1c33052e08dad"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34098.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-34098",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 498262,
  "published_at": "2026-07-01T16:04:04.525+00:00"
}