Discourse chat messages susceptible to Cross-site Scripting through chat excerpts

{
  "id": "ee5a7e5305cdf73ffd2ea32c564b679c259388042e69ef616141e69031a4005c",
  "url": "https://osv.dev/vulnerability/CVE-2023-26040",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Discourse chat messages susceptible to Cross-site Scripting through chat excerpts",
    "summary": "Discourse is an open-source discussion platform. Between versions 3.1.0.beta2 and 3.1.0.beta3 of the `tests-passed` branch, editing or responding to a chat message containing malicious content could lead to a cross-site scripting attack. This issue is patched in version 3.1.0.beta3 of the `tests-passed` branch. There are no known workarounds.",
    "evidence": "osv:CVE-2023-26040",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2023-26040",
      "aliases": [
        "BIT-discourse-2023-26040",
        "CVE-2023-26040",
        "GHSA-ccfc-qpmp-gq87"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/discourse/discourse",
              "type": "GIT",
              "events": [
                {
                  "introduced": "e6a41150e24f3163d61d32f86834acae8098dead"
                },
                {
                  "fixed": "a373bf2a01488c206e7feb28a9d2361b22ce6e70"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:discourse:discourse:3.1.0:beta2:*:*:beta:*:*:*",
                    "range": [
                      {
                        "introduced": "3.1.0-beta2"
                      },
                      {
                        "last_affected": "3.1.0-beta2"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "range": [
                      {
                        "fixed": "a373bf2a01488c206e7feb28a9d2361b22ce6e70"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "3.1.0-beta2",
            "v3.1.0.beta2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-26040.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.185766790Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/26xxx/CVE-2023-26040.json",
        "https://github.com/discourse/discourse/security/advisories/GHSA-ccfc-qpmp-gq87",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-26040",
        "https://github.com/discourse/discourse/commit/a373bf2a01488c206e7feb28a9d2361b22ce6e70"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "tests-passed > 3.1.0.beta2, < 3.1.0.beta3"
                  },
                  {
                    "last_affected": "tests-passed > 3.1.0.beta2, < 3.1.0.beta3"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandaloneSingleVersion"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/26xxx/CVE-2023-26040.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-26040",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 518330,
  "published_at": "2023-03-17T14:45:35.889+00:00"
}