CVE-2021-20241

Process crash via zero JP2 sampling divisors

Published Mar 9, 2021 · Updated Aug 3, 2024

Divide-by-zero in ImageMagick 6 before 6.9.11-62 and ImageMagick 7 before 7.0.10-62 allows local users to crash JP2 encoding via a crafted file. WriteJP2Image computes a component-buffer offset by directly dividing coordinates and image width by JP2 dx and dy sampling factors without guarding zero values. Exploitation requires a user or automated workflow to process the file, and the reported consequence is interruption of the ImageMagick process.

CVSS severity5.5
Medium
EPSS probability1.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Divide-by-zero in ImageMagick 6 before 6.9.11-62 and ImageMagick 7 before 7.0.10-62 allows local users to crash JP2 encoding via a crafted file. WriteJP2Image computes a component-buffer offset by directly dividing coordinates and image width by JP2 dx and dy sampling factors without guarding zero values. Exploitation requires a user or automated workflow to process the file, and the reported consequence is interruption of the ImageMagick process.

The record

CVE
CVE-2021-20241
Published
Mar 9, 2021
Updated
Aug 3, 2024
Vendor
ImageMagick Studio LLC
Product
ImageMagick
Classifications
CWE-369, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=ImageMagick 6.9.11-62, ImageMagick 7.0.10-62

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

ImageMagick Studio LLC · ImageMagickversion=ImageMagick 6.9.11-62, ImageMagick 7.0.10-62

Published CVSS scores

5.5CanonicalCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-369Divide By Zero
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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