GHSA-gxhx-g4fq-49hj is a medium-severity (CVSS 6.8) Cross-site Scripting (XSS) vulnerability in carrierwave. A fix is available for carrierwave — see the affected versions and patch details below.
CarrierWave Content-Type allowlist bypass vulnerability, possibly leading to XSS
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-gxhx-g4fq-49hj.
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.
How urgent is this, really
GHSA-gxhx-g4fq-49hj plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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
Impact
CarrierWave::Uploader::ContentTypeAllowlist 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.
In addition, by setting the Content-Type configured by the attacker at the time of file delivery, it is possible to cause XSS on the user's browser when the uploaded file is opened.
Patches
Workarounds
When validating with allowlisted_content_type? in CarrierWave::Uploader::ContentTypeAllowlist , forward match(\A) the Content-Type set in content_type_allowlist, preventing unintentional permission of text/html;image/png when you want to allow only image/png in content_type_allowlist.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | carrierwave | ≥ 3.0.0&&< 3.0.5 | 3.0.5bundle update carrierwave --conservative |
| 💎RubyGems | carrierwave | all versions | 2.2.5bundle update carrierwave --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for carrierwave, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update carrierwave to 3.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gxhx-g4fq-49hj 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 GHSA-gxhx-g4fq-49hj can be triaged on real exposure rather than presence alone.
Tailored to GHSA-gxhx-g4fq-49hj. 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-gxhx-g4fq-49hj in your dependencies?
O3 Security finds GHSA-gxhx-g4fq-49hj across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.