GHSA-g3gw-q23r-pgqm
HIGHyt-dlp: Arbitrary Command Injection when using the `--netrc-cmd` option
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
yt-dlpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
When yt-dlp's --netrc-cmd command-line option (or netrc_cmd Python API parameter) is used, an attacker could achieve arbitrary command injection on the user's system with a maliciously crafted URL.
Impact
yt-dlp maintainers assume the impact of this vulnerability to be high for anyone who uses --netrc-cmd in their command/configuration or netrc_cmd in their Python scripts. Even though the maliciously crafted URL itself will look very suspicious to many users, it would be trivial for a maliciously crafted webpage with an inconspicuous URL to covertly exploit this vulnerability via HTTP redirect. Users without --netrc-cmd in their arguments or netrc_cmd in their scripts are unaffected. No evidence has been found of this exploit being used in the wild.
Patches
yt-dlp version 2026.02.21 fixes this issue by validating all netrc "machine" values and raising an error upon unexpected input.
Workarounds
It is recommended to upgrade yt-dlp to version 2026.02.21 as soon as possible.
Users who are unable to upgrade should avoid using the --netrc-cmd command-line option (or netrc_cmd Python API parameter), or they should at least not pass a placeholder ({}) in their --netrc-cmd argument.
Details
yt-dlp's --netrc-cmd option can be used to run any arbitrary shell command to retrieve site login credentials so that the user doesn't have to store the credentials as plaintext in the filesystem. The --netrc-cmd argument is a shell command with an optional placeholder ({}). If the placeholder is present in the argument, it is replaced with the netrc "machine" value, which specifies the site for which login credentials are needed.
The netrc "machine" value is usually explicitly defined in yt-dlp's extractor code for a given site. However, yt-dlp has four extractors where the netrc "machine" value needs to be dynamically sourced from the site's hostname. And in three of those extractors (GetCourseRuIE, TeachableIE and TeachableCourseIE), wildcard matches are allowed for one or more subdomains of the hostname. This can result in a netrc "machine" value that contains special shell characters.
The --netrc-cmd argument is executed by a modified version of Python's subprocess.Popen with shell=True, which means that any special characters may be interpreted by the host shell, potentially leading to arbitrary command injection.
Here is an example of maliciously crafted URL input that exploits the vulnerability:
> yt-dlp --netrc-cmd "echo {}" "https://;echo pwned>&2;#.getcourse.ru/video"
[GetCourseRu] Executing command: echo getcourseru
WARNING: [GetCourseRu] Failed to parse .netrc: bad toplevel token 'getcourseru' (-, line 2)
[GetCourseRu] Extracting URL: https://;echo pwned>&2;#.getcourse.ru/video
[GetCourseRu] Executing command: echo ;echo pwned>&2;
pwned
[GetCourseRu] No authenticators for ;echo pwned>&2;
[GetCourseRu] video: Downloading webpage
Although only 3 of yt-dlp's extractors are directly susceptible to this attack, yt-dlp's "generic" extractor will follow HTTP redirects and try to match the resulting URL with one of the dedicated extractors. This means that any URL processed by the generic extractor could ultimately lead to a maliciously crafted URL that is matched by one of the vulnerable extractors. Hypothetically, an attacker could create a website with an inconspicuous URL and legitimate-looking media content that would serve an HTTP redirect to a maliciously crafted URL when it detects a request from yt-dlp.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | yt-dlp | ≥ 2023.06.21&&< 2026.02.21 | 2026.02.21 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for yt-dlp. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update yt-dlp to 2026.02.21 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g3gw-q23r-pgqm is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-g3gw-q23r-pgqm is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-g3gw-q23r-pgqm. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-g3gw-q23r-pgqm in your dependencies?
O3 detects GHSA-g3gw-q23r-pgqm across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.