CVE-2026-4756: Android-ImageMagick7 Buffer Overflow Flaw

CVE-2026-4756 Overview

An Out-of-bounds Write vulnerability has been identified in MolotovCherry Android-ImageMagick7, a popular Android port of the ImageMagick image processing library. This memory corruption flaw allows attackers to write data beyond the boundaries of allocated memory buffers, potentially leading to arbitrary code execution or system crashes on affected Android devices.

Critical Impact

Successful exploitation could allow attackers to execute arbitrary code with the privileges of the application using the vulnerable library, potentially compromising confidentiality, integrity, and availability of the affected Android device.

Affected Products

• MolotovCherry Android-ImageMagick7 versions before 7.1.2-11

Discovery Timeline

• 2026-03-24 - CVE-2026-4756 published to NVD
• 2026-03-26 - Last updated in NVD database

Technical Details for CVE-2026-4756

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-bounds Write), a memory corruption issue that occurs when software writes data past the end of an allocated buffer or before the beginning of a buffer. In the context of Android-ImageMagick7, this flaw can be triggered when processing specially crafted image files.

The attack requires local access and user interaction, meaning an attacker would need to convince a user to open a malicious image file using an application that relies on the vulnerable Android-ImageMagick7 library. Once triggered, the out-of-bounds write could corrupt adjacent memory structures, potentially allowing an attacker to hijack program execution flow.

Root Cause

The root cause stems from improper boundary checking during image processing operations within the Android-ImageMagick7 library. When handling certain image data structures, the library fails to properly validate buffer sizes before write operations, allowing data to be written beyond the allocated memory region.

Attack Vector

The attack vector is local, requiring user interaction to exploit. An attacker would craft a malicious image file designed to trigger the out-of-bounds write condition when processed by an application using the vulnerable library. The attack scenario typically involves:

1. Attacker creates a specially crafted image file containing malformed data
2. Victim receives the image through various channels (messaging apps, email, downloads)
3. Victim opens the image with an application using Android-ImageMagick7
4. The malformed image triggers the out-of-bounds write during processing
5. Attacker potentially achieves code execution within the application context

The vulnerability manifests during image processing operations where boundary validation is insufficient. Technical details regarding the specific vulnerable code paths can be found in the GitHub Pull Request #194.

Detection Methods for CVE-2026-4756

Indicators of Compromise

• Unexpected application crashes when processing image files
• Abnormal memory consumption patterns in applications using Android-ImageMagick7
• Application behavior anomalies following image file operations
• Log entries indicating memory access violations or segmentation faults

Detection Strategies

• Implement application crash monitoring to detect potential exploitation attempts
• Monitor for unusual image file processing activities across mobile device fleets
• Deploy mobile threat detection solutions capable of identifying memory corruption exploits
• Review application dependencies to identify usage of vulnerable Android-ImageMagick7 versions

Monitoring Recommendations

• Enable crash reporting and telemetry for applications using the Android-ImageMagick7 library
• Monitor application sandboxes for signs of privilege escalation or unusual behavior
• Track network traffic for delivery of potentially malicious image files
• Implement file integrity monitoring for critical application components

How to Mitigate CVE-2026-4756

Immediate Actions Required

• Update Android-ImageMagick7 to version 7.1.2-11 or later immediately
• Audit all applications in your environment that depend on Android-ImageMagick7
• Implement input validation for image files before processing with the library
• Consider temporarily disabling image processing features in affected applications until patched

Patch Information

The vulnerability has been addressed in Android-ImageMagick7 version 7.1.2-11. The fix is available through the official GitHub repository. Developers should update their dependencies to incorporate the patched version. For detailed information about the fix, refer to GitHub Pull Request #194.

Workarounds

• Restrict processing of image files from untrusted sources until the patch is applied
• Implement additional input validation and sanitization for image files before processing
• Run applications using Android-ImageMagick7 with minimum required permissions
• Consider using alternative image processing libraries temporarily if immediate patching is not possible

# Update Android-ImageMagick7 dependency in build.gradle
# Change version to 7.1.2-11 or later in your project dependencies
# Example gradle dependency update:
implementation 'com.github.MolotovCherry:Android-ImageMagick7:7.1.2-11'