GHSA-vfmv-jfc5-pjjw
CarrierWave content-Type allowlist bypass vulnerability which possibly leads to XSS remained
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| RubyGems | carrierwave | >= 3.0.0, < 3.0.7 | 3.0.7 |
| RubyGems | carrierwave | < 2.2.6 | 2.2.6 |
Details
As written in the advisory (Markdown source, shown as plain text).
### Impact
The vulnerability [CVE-2023-49090](https://github.com/carrierwaveuploader/carrierwave/security/advisories/GHSA-gxhx-g4fq-49hj) wasn't fully addressed.
This vulnerability is caused by the fact that when uploading to object storage, including Amazon S3, it is possible to set a Content-Type value that is interpreted by browsers to be different from what's allowed by `content_type_allowlist`, by providing multiple values separated by commas.
This bypassed value can be used to cause XSS.
### Patches
Upgrade to [3.0.7](https://rubygems.org/gems/carrierwave/versions/3.0.7) or [2.2.6](https://rubygems.org/gems/carrierwave/versions/2.2.6).
### Workarounds
Use the following monkey patch to let CarrierWave parse the Content-type by using `Marcel::MimeType.for`.
```ruby
# For CarrierWave 3.x
CarrierWave::SanitizedFile.class_eval do
def declared_content_type
@declared_content_type ||
if @file.respond_to?(:content_type) && @file.content_type
Marcel::MimeType.for(declared_type: @file.content_type.to_s.chomp)
end
end
end
```
```ruby
# For CarrierWave 2.x
CarrierWave::SanitizedFile.class_eval do
def existing_content_type
if @file.respond_to?(:content_type) && @file.content_type
Marcel::MimeType.for(declared_type: @file.content_type.to_s.chomp)
end
end
end
```
### References
[OWASP - File Upload Cheat Sheet](https://cheatsheetseries.owasp.org/cheatsheets/File_Upload_Cheat_Sheet.html#content-type-validation)
References
External links from the advisory. They lead to third-party sites.
- https://github.com/carrierwaveuploader/carrierwave/security/advisories/GHSA-vfmv-jfc5-pjjw
- https://nvd.nist.gov/vuln/detail/CVE-2024-29034
- https://github.com/carrierwaveuploader/carrierwave/commit/25b1c800d45ef8e78dc445ebe3bd8a6e3f0a3477
- https://github.com/carrierwaveuploader/carrierwave
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/carrierwave/CVE-2024-29034.yml