CVE-2023-49090 is a medium-severity (CVSS 6.8) Cross-site Scripting (XSS) vulnerability in carrierwave. O3 Security confirms whether CVE-2023-49090 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
CarrierWave has a content-type allowlist bypass vulnerability, possibly leading to XSS
Real-World Exposure
carrierwave💎carrierwaveReal-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
CarrierWave is a solution for file uploads for Rails, Sinatra and other Ruby web frameworks. CarrierWave has a Content-Type allowlist bypass vulnerability, possibly leading to XSS. The validation in allowlisted_content_type? determines Content-Type permissions by performing a partial match. If the content_type argument of allowlisted_content_type? is passed a value crafted by the attacker, Content-Types not included in the content_type_allowlist will be allowed. This issue has been patched in versions 2.2.5 and 3.0.5.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | carrierwave | ≥ 3.0.0&&< 3.0.5 | 3.0.5 |
| 💎RubyGems | carrierwave | all versions | 2.2.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for carrierwave. 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 carrierwave to 3.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-49090 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-2023-49090 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-2023-49090. 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-2023-49090 in your dependencies?
O3 detects CVE-2023-49090 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.