Which products and versions are affected by CVE-2021-33564?

Affected: Dragonfly (Dragonfly Project). The full list is in the CVE brief.

Is CVE-2021-33564 being exploited in the wild?

It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Oct 14, 2023.

Is CVE-2021-33564 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2021-33564?

No public exploit code is known.

Is there a fix for CVE-2021-33564?

Fixed versions are available, including Dragonfly 1.4.0.

How urgently should CVE-2021-33564 be patched?

Brandefense priority: patch immediately, because it is listed as exploited in the wild.

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Vulnerability Intelligence

CVE-2021-33564

CriticalExploited

Dragonfly contains remote code execution vulnerability

Published Jun 2, 2021 · Updated Jul 8, 2026 · Also known as GHSA-j858-xp5v-f8xx

Key Facts

Patch immediately

CVE-2021-33564 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Dragonfly (Dragonfly Project).
It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Oct 14, 2023. No public exploit code is known.
EPSS estimates a 72% probability of exploitation in the next 30 days.
Fixed versions are available, including Dragonfly 1.4.0.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v3.1

9.8

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS (30-day exploit likelihood)

72%

Higher than 99.4% of all scored CVEs

Exploited in the wild

Yes

2 catalog listings

Public exploit code

None known

Get the full CVE-2021-33564 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

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.

Known-Exploited Catalog Listings

Catalog	Added	Remediation due	Ransomware use
Industry KEV feed	Nov 29, 2023	n/a	Not reported
CIRCL KEV	Oct 14, 2023	n/a	Not reported

Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Affected Products

2 affected entries in total

Product	Affected versions	Fixed in
DragonflyDragonfly Project	See advisory	1.4.0

Patched Releases

Dragonfly

1.4.0

Timeline

Publicly disclosed
Jun 2, 2021
Added to CIRCL KEV
Oct 14, 2023
Added to Industry KEV feed
Nov 29, 2023
Last updated
Jul 8, 2026

Weakness Type

CWE-88 Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')
CWE-94 Improper Control of Generation of Code ('Code Injection')

References

advisoryGHSA advisory
advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2021-33564
exploitVulnCheck exploitation report
exploitVulnCheck exploitation report
exploitVulnCheck exploitation report

15 more references in the full CVE brief

FAQ

Common Questions.

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.
Affected: Dragonfly (Dragonfly Project). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Oct 14, 2023.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Dragonfly 1.4.0.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

Is CVE-2021-33564 Running On Your Attack Surface?

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