Heap Buffer Overflow in ImageMagick Despeckle Causes Out-of-Bounds Write

Publication date: 2026-04-13

Last updated on: 2026-04-17

Assigner: GitHub, Inc.

Description

ImageMagick is free and open-source software used for editing and manipulating digital images. In versions below both 7.1.2-19 and 6.9.13-44, an integer overflow in the despeckle operation causes a heap buffer overflow on 32-bit builds that will result in an out of bounds write. This issue has been fixed in versions 6.9.13-44 and 7.1.2-19.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-04-13

Last Modified

2026-04-17

Generated

2026-07-06

AI Q&A

2026-04-14

EPSS Evaluated

2026-07-05

NVD

CVE-2026-34238

Affected Vendors & Products

Vendor	Product	Version / Range
imagemagick	imagemagick	to 6.9.13-44 (exc)
imagemagick	imagemagick	From 7.0.0-0 (inc) to 7.1.2-19 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-190	The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
CWE-787	The product writes data past the end, or before the beginning, of the intended buffer.

Attack-Flow Graph

Executive Summary

This vulnerability exists in ImageMagick versions below 7.1.2-19 and 6.9.13-44. It is caused by an integer overflow in the despeckle operation, which leads to a heap buffer overflow on 32-bit builds. This overflow results in an out of bounds write, potentially corrupting memory.

Impact Analysis

The heap buffer overflow caused by this vulnerability can lead to memory corruption, which may cause the application to crash or behave unpredictably. Although the CVSS score indicates no impact on confidentiality or integrity, it has a high impact on availability, meaning it can cause denial of service by crashing the software.

Mitigation Strategies

To mitigate this vulnerability, you should upgrade ImageMagick to version 7.1.2-19 or later, or version 6.9.13-44 or later, as these versions contain the fix for the integer overflow and heap buffer overflow issue in the despeckle operation.

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