GHSA-3V33-3WMW-3785

Workarounds

It is recommended to upgrade yt-dlp to version 2024.07.07 as soon as possible.

For users not able to upgrade:

• Avoid using the Douyu extractors (--ies default,-douyutv,-douyushow)
• Uninstall (or do not install) PhantomJS

Acknowledgement

Thanks to @LeSuisse for reporting this promptly after bootcdn.net was discovered to be under control of the same bad actor behind the polyfill.io supply chain attack.

References

• https://github.com/yt-dlp/yt-dlp/commit/6075a029dba70a89675ae1250e7cdfd91f0eba41
• https://sansec.io/research/polyfill-supply-chain-attack

yt-dlp's DouyuTV and DouyuShow extractors used a cdn.bootcdn.net URL as a fallback for fetching a component of the crypto-js JavaScript library. When the Douyu extractor is used, yt-dlp extracts this JavaScript code and attempts to execute it externally using PhantomJS. bootcdn.net is owned by the bad actor responsible for the Polyfill JS supply chain attack that has been ongoing since at least June 2023. While there is no evidence that PhantomJS has been targeted by or is vulnerable to any attacks carried out by the Polyfill JS actor, there is the possibility that malicious JavaScript code may have been downloaded/cached by yt-dlp or executed by PhantomJS.

In order for this potential vulnerability to be exploited by any hypothetical attack, all 3 of the following conditions must be met:

1. The user has PhantomJS installed on their system.
2. The user passes a douyu.com or douyutv.com URL to yt-dlp as input, or passes a URL that redirects to one of these domains.
3. cdnjs.cloudflare.com is unavailable or blocked at the time of extraction, necessitating the usage of the cdn.bootcdn.net fallback; or it had been unavailable during a previous run of the Douyu extractor and JavaScript code from cdn.bootcdn.net had been cached to disk.

Kodem intelligence

yt-dlp version 2024.07.07 fixes this issue by removing the URL pointing to the malicious CDN and by invalidating any Douyu extractor cache data created by unpatched versions of yt-dlp.

1. What is GHSA-3V33-3WMW-3785? GHSA-3V33-3WMW-3785 is a low-severity security vulnerability in yt-dlp (pip), affecting versions >= 2023.09.24, < 2024.07.07. It is fixed in 2024.07.07.
2. Which versions of yt-dlp are affected by GHSA-3V33-3WMW-3785? yt-dlp (pip) versions >= 2023.09.24, < 2024.07.07 is affected.
3. Is there a fix for GHSA-3V33-3WMW-3785? Yes. GHSA-3V33-3WMW-3785 is fixed in 2024.07.07. Upgrade to this version or later.
4. Is GHSA-3V33-3WMW-3785 exploitable, and should I be worried? Whether GHSA-3V33-3WMW-3785 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
5. What actually determines whether GHSA-3V33-3WMW-3785 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
6. How do I fix GHSA-3V33-3WMW-3785? Upgrade yt-dlp to 2024.07.07 or later.