CVE-2021-33564

Public Exploit

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 91.36% Top 5%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory githubusercontent.com Third-Party Advisory co.nz
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/markevans/dragonfly/issues/513 issue tracking third party advisory
https://github.com/markevans/dragonfly/commit/25399297bb457f7fcf8e3f91e85945b255b111b5 third party advisory patch
https://github.com/markevans/dragonfly/compare/v1.3.0...v1.4.0 third party advisory patch
https://raw.githubusercontent.com/projectdiscovery/nuclei-templates/master/cves/2021/CVE-2021-33564.yaml third party advisory exploit
https://github.com/mlr0p/CVE-2021-33564 third party advisory exploit
https://zxsecurity.co.nz/research/argunment-injection-ruby-dragonfly/ third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-33564?
CVE-2021-33564 has been scored as a critical severity vulnerability.
How to fix CVE-2021-33564?
To fix CVE-2021-33564, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-33564 being actively exploited in the wild?
It is possible that CVE-2021-33564 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~91% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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