Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin

{
  "id": "b736d827924076d456ed3d6cc349f1353974740b5792bba60e04839ee599f900",
  "url": "https://osv.dev/vulnerability/CVE-2026-87995",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin",
    "summary": "Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.8.11 until 0.11.1, src/lib/components/chat/FileNav/PortPreview.svelte rendered terminal port content in an iframe sandbox containing both allow-scripts and allow-same-origin. Because the terminal proxy serves that content from the Open WebUI origin, an authenticated user with access to a shared terminal server could host script on a previewed port and take over a victim's account when the victim opened the preview. This issue is fixed in version 0.11.1.",
    "evidence": "osv:CVE-2026-87995",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-87995",
      "aliases": [
        "CVE-2026-87995",
        "GHSA-jmc6-2wr8-h3wj",
        "PYSEC-2026-4123"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/open-webui/open-webui",
              "type": "GIT",
              "events": [
                {
                  "introduced": "4d058a125b17eb57212af5eab98d683548d546e3"
                },
                {
                  "fixed": "d3e8bf3405e848cfba377814d0aa7ba7290e414d"
                },
                {
                  "fixed": "54d7a223707f03172efbb9e754db6e69709956d0"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0.8.11"
                      },
                      {
                        "fixed": "0.11.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "54d7a223707f03172efbb9e754db6e69709956d0"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "d3e8bf3405e848cfba377814d0aa7ba7290e414d"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v0.11.1"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.11.0",
            "v0.10.2",
            "v0.10.1",
            "v0.10.0",
            "v0.9.5",
            "v0.9.4",
            "v0.9.3",
            "v0.9.2",
            "v0.9.1",
            "v0.9.0",
            "v0.8.12",
            "v0.8.11"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-87995.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:51.082398811Z",
      "provider": "osv",
      "references": [
        "https://github.com/open-webui/open-webui/releases/tag/v0.11.1",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/87xxx/CVE-2026-87995.json",
        "https://github.com/open-webui/open-webui/security/advisories/GHSA-jmc6-2wr8-h3wj",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-87995",
        "https://github.com/open-webui/open-webui/commit/54d7a223707f03172efbb9e754db6e69709956d0"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-1021",
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/87xxx/CVE-2026-87995.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-87995",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 519695,
  "published_at": "2026-09-09T21:26:30.89+00:00"
}