CVE-2024-47220 is a high-severity (CVSS 7.5) vulnerability in webrick. A fix is available for webrick — see the affected versions and patch details below.
HTTP Request Smuggling in ruby webrick
Real-World Exposure
webrickReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
An issue was discovered in the WEBrick toolkit through 1.8.1 for Ruby. It allows HTTP request smuggling by providing both a Content-Length header and a Transfer-Encoding header, e.g., "GET /admin HTTP/1.1\r\n" inside of a "POST /user HTTP/1.1\r\n" request. NOTE: the supplier's position is "Webrick should not be used in production."
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | webrick | all versions | 1.8.2bundle update webrick --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for webrick, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update webrick to 1.8.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-47220 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-47220 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-47220. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This CVE is rated as having Moderate impact because Webrick should not be used in production. It is only still maintained because there are other gems relying on it, most of which do so only for testing, and only because it is a pure ruby implementation and it was shipped with Ruby in the past.
| Product | Fixed in | Advisory |
|---|---|---|
| RHOL-5.9-RHEL-9 | openshift-logging/cluster-logging-operator-bundle:v5.9.11-25 | RHSA-2025:1227 |
Frequently Asked Questions
Is CVE-2024-47220 in your dependencies?
O3 Security finds CVE-2024-47220 across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.