An argument injection vulnerability in the Dragonfly gem before 1.4.0 for Ruby allows remote attackers to read and write to arbitrary files via a crafted URL when the verify_url option is disabled. This may lead to code execution. The problem occurs because the generate and process features mishandle use of the ImageMagick convert utility.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-33564
• markevans/dragonfly#513
• markevans/dragonfly@2539929
• markevans/dragonfly@v1.3.0...v1.4.0
• https://github.com/mlr0p/CVE-2021-33564
• https://raw.githubusercontent.com/projectdiscovery/nuclei-templates/master/cves/2021/CVE-2021-33564.yaml
• https://zxsecurity.co.nz/research/argunment-injection-ruby-dragonfly/
• GHSA-j858-xp5v-f8xx
• https://github.com/rubysec/ruby-advisory-db/blob/master/gems/dragonfly/CVE-2021-33564.yml