CVE-2021-33564

mediumpriority · attend · 74EPSS 0.721 · 99 %ileexploit · PoCEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

2 exploits · PoC

Likely / severe?

72.1% (99th) EPSS

CVSS 6.8 · medium

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6.8–9.8

v2.06.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · OSV

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-88USprimaryCWE-88USCWE-94US

exploits (2)

Public proof-of-concept and weaponised exploit code.

dorkerdevil/CVE-2021-33564Argument Injection in Dragonfly Ruby Gem exploit (backup)PoC · poc_in_github
mlr0p/CVE-2021-33564Argument Injection in Dragonfly Ruby GemPoC · poc_in_github

affected products (3)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
dragonfly project dragonfly< 1.4.0nvdUScpe:2.3:a:dragonfly_project:dragonfly:*:*:*:*:*:*:*:*
RubyGems dragonfly< 1.4.0osvUSpkg:gem/dragonfly

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-j858-xp5v-f8xxDragonfly contains remote code execution vulnerability2021-06-02ghsa · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-05-29modified 2026-06-17

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+587 more

references (19)

External citations — patches, advisories, analysis.

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