CVE-2026-55404 is a high-severity (CVSS 7.5) CWE-74 vulnerability in yt-dlp. O3 Security confirms whether CVE-2026-55404 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
yt-dlp: Downstream command injection via improper sanitization of yt-dlp --write-link output
Real-World Exposure
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
yt-dlp and youtube-dl are command-line audio/video downloaders. Prior to 2026.7.4, the --write-link, --write-url-link, and --write-desktop-link options can write .url or .desktop shortcut files using attacker-controlled webpage_url or filename metadata without sufficient validation or escaping, allowing malicious file:// URI injection on Windows or newline-based desktop entry key injection on Linux that can execute commands if the generated shortcut is opened. This issue is fixed in version 2026.7.4.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | yt-dlp | all versions | 2026.7.4 |
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 2026.7.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55404 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 CVE-2026-55404 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 CVE-2026-55404. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-55404 in your dependencies?
O3 detects CVE-2026-55404 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.