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GHSA-F7J3-774F-RFHJ

Vulnerability from github – Published: 2026-06-16 20:16 – Updated: 2026-07-20 13:45
VLAI
Summary
yt-dlp: File Downloader cookie leak with curl
Details

Summary

If curl is used an external downloader for yt-dlp, cookies may be leaked to an unintended host upon HTTP redirect or when the host for download fragments differs from their parent manifest's.

This is the equivalent to GHSA-v8mc-9377-rwjj for the curl downloader. The vulnerable behavior is present in yt-dlp released since 2023.09.24.

Details

At the file download stage, the cookies are passed by yt-dlp to the file downloader via --cookie. However, unless these are loaded from a file, this operation does not activate the cookie engine. As a result, curl will send cookies with requests to domains or paths for which the cookies are not scoped.

An example of a potential attack scenario exploiting this vulnerability: 1. an attacker has crafted a malicious website with an embedded URL designed to be detected by yt-dlp as a video download. This embedded URL has the domain of a trusted site that the user has loaded cookies for, and conducts an unvalidated redirect to a target URL. 2. yt-dlp extracts this URL and calculates the cookies which are then passed to curl. 3. the download URL redirects to a server controlled by the attacker, to which curl forwards the user's sensitive cookie information.

Patches

yt-dlp version 2026.06.09 fixes this issue by doing the following:

  • Pass the cookies through stdin via --cookie - if curl is version 7.59 or higher.
  • Pass the cookies via --cookie /dev/fd/0 if the system supports this device file.
  • In all other cases create a temporary file, save the cookies and then pass via --cookie <file>.

Workarounds

It is recommended to upgrade yt-dlp to version 2026.06.09 as soon as possible.

For users who are not able to upgrade:

  • Do not use --downloader curl.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:N/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "yt-dlp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2023.9.24"
            },
            {
              "fixed": "2026.6.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-50019"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-200"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-16T20:16:56Z",
    "nvd_published_at": "2026-06-23T17:17:02Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\nIf curl is used an external downloader for yt-dlp, cookies may be leaked to an unintended host upon HTTP redirect or when the host for download fragments differs from their parent manifest\u0027s.\n\nThis is the equivalent to [GHSA-v8mc-9377-rwjj](\u003chttps://github.com/yt-dlp/yt-dlp/security/advisories/GHSA-v8mc-9377-rwjj\u003e) for the `curl` downloader. The vulnerable behavior is present in [yt-dlp](https://github.com/yt-dlp/yt-dlp) released since 2023.09.24.\n\n### Details\nAt the file download stage, the cookies are passed by yt-dlp to the file downloader via `--cookie`. However, unless these are loaded from a file, this operation does not activate the cookie engine. As a result, `curl` will send cookies with requests to domains or paths for which the cookies are not scoped.\n\nAn example of a potential attack scenario exploiting this vulnerability:\n1. an attacker has crafted a malicious website with an embedded URL designed to be detected by yt-dlp as a video download. This embedded URL has the domain of a trusted site that the user has loaded cookies for, and conducts an [unvalidated redirect](https://cheatsheetseries.owasp.org/cheatsheets/Unvalidated_Redirects_and_Forwards_Cheat_Sheet.html) to a target URL.\n2. yt-dlp extracts this URL and calculates the cookies which are then passed to `curl`.\n3. the download URL redirects to a server controlled by the attacker, to which `curl` forwards the user\u0027s sensitive cookie information.\n\n### Patches\nyt-dlp version 2026.06.09 fixes this issue by doing the following:\n\n- Pass the cookies through stdin via `--cookie -` if `curl` is version 7.59 or higher.\n- Pass the cookies via `--cookie /dev/fd/0` if the system supports this device file.\n- In all other cases create a temporary file, save the cookies and then pass via `--cookie \u003cfile\u003e`.\n\n### Workarounds\nIt is recommended to upgrade yt-dlp to version 2026.06.09 as soon as possible.\n\nFor users who are not able to upgrade:\n\n- Do not use `--downloader curl`.",
  "id": "GHSA-f7j3-774f-rfhj",
  "modified": "2026-07-20T13:45:40Z",
  "published": "2026-06-16T20:16:56Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/yt-dlp/yt-dlp/security/advisories/GHSA-f7j3-774f-rfhj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-50019"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yt-dlp/yt-dlp/commit/2726572520238356bcf64aba2040228648b44c82"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-f7j3-774f-rfhj"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/yt-dlp/PYSEC-2026-3431.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/yt-dlp/yt-dlp"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yt-dlp/yt-dlp-nightly-builds/releases/tag/2026.06.09.230517"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yt-dlp/yt-dlp/releases/tag/2026.06.09"
    },
    {
      "type": "WEB",
      "url": "https://pypi.org/project/yt-dlp"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "yt-dlp: File Downloader cookie leak with curl "
}



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