{"id":"CVE-2021-33564","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-33564","generatedAt":"2026-10-27T22:26:21.463Z","title":"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.","description":"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.","published":"2021-05-29T14:15:09.000Z","lastModified":"2026-06-17T03:54:48.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-88"],"affected":["dragonfly project/dragonfly"],"epss":{"score":0.72143,"percentile":0.99429,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 72.1%, higher than 99% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"https://github.com/markevans/dragonfly/commit/25399297bb457f7fcf8e3f91e85945b255b111b5","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/markevans/dragonfly/compare/v1.3.0...v1.4.0","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/markevans/dragonfly/issues/513","tags":["Issue Tracking","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/mlr0p/CVE-2021-33564","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://raw.githubusercontent.com/projectdiscovery/nuclei-templates/master/cves/2021/CVE-2021-33564.yaml","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://zxsecurity.co.nz/research/argunment-injection-ruby-dragonfly/","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/markevans/dragonfly/commit/25399297bb457f7fcf8e3f91e85945b255b111b5","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/markevans/dragonfly/compare/v1.3.0...v1.4.0","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/markevans/dragonfly/issues/513","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/mlr0p/CVE-2021-33564","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://raw.githubusercontent.com/projectdiscovery/nuclei-templates/master/cves/2021/CVE-2021-33564.yaml","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://zxsecurity.co.nz/research/argunment-injection-ruby-dragonfly/","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-33564","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}