Stored XSS in Direct Messages via Prompt Sharing in parisneo/lollms

{
  "id": "b2f8bc8e619a6737df16be8580577f499d29e5dc4f8a382c930ce580e87f7e79",
  "url": "https://osv.dev/vulnerability/CVE-2026-12228",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Stored XSS in Direct Messages via Prompt Sharing in parisneo/lollms",
    "summary": "A stored cross-site scripting (XSS) vulnerability exists in the `POST /api/prompts/share` endpoint of parisneo/lollms (latest version). The endpoint stores attacker-controlled `prompt_content` into `DBDirectMessage.content` without server-side sanitization. When a victim opens the direct message (DM) thread, the message is rendered by the DM UI through `MessageContentRenderer`, which uses `v-html` to insert rendered HTML into the DOM. The frontend sanitizer, which is regex-based, fails to comprehensively sanitize attacker-controlled HTML, allowing malicious payloads to execute in the victim's browser context. This vulnerability enables any authenticated user to send a malicious prompt-share message to another user's inbox, leading to arbitrary JavaScript execution, authenticated actions as the victim, exposure of same-origin application data, and potential account takeover.",
    "evidence": "osv:CVE-2026-12228",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-12228",
      "aliases": [
        "CVE-2026-12228"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/parisneo/lollms",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "a9b21a0c417f8a67bc221c699cfae8c75068ed90"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:lollms:lollms:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "2.1.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.1.0",
            "v2.0.0",
            "v1.0.1",
            "v1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-12228.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:23.768195752Z",
      "provider": "osv",
      "references": [
        "https://huntr.com/bounties/25623635-5ceb-4062-8289-02089e6d97c1",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12228.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-12228"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "@huntr_ai",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12228.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-12228",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 490279,
  "published_at": "2026-07-18T20:36:36.906+00:00"
}