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ExploitedNot in CISA KEV yetFix available

CVE-2021-33564

Exploitation confirmed. First attested on 2023-10-14 by GCVE · kevintel, GCVE · shadowserver.

  • Published2021-05-29
  • Fixed in1.4.0
  • WeaknessCWE-88

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC
  1. 2021-05-2914:15CVE publishedNVD
  2. 2023-10-1417:23Listed as exploited by GCVEGCVE
  3. 2023-10-1417:23Exploitation first reportedGCVE

Versions per branch

NVD · OSV
Dragonfly project dragonfly
BranchAffectedFixed in
1.4< 1.4.01.4.0

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

  1. Update Dragonfly project dragonfly to 1.4.0

Advisories and patches

Detection

read 2026-11-01 01:02 UTC
Nuclei template
available
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2021-05-29
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-j858-xp5v-f8xx

Frequently asked questions

What is CVE-2021-33564?

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.

Is CVE-2021-33564 actively exploited?

Active exploitation of CVE-2021-33564 has not been confirmed. Its EPSS score was 72.1% on 2026-11-04, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-33564?

CVE-2021-33564 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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