CVE-2026-25970: ImageMagick Has Signed Integer Overflow in SIXEL Decoder, Leading to Memory Corruption

March 12, 2026

A signed integer overflow vulnerability in ImageMagick’s SIXEL decoder allows an attacker to trigger memory corruption and denial of service when processing a maliciously crafted SIXEL image file. The vulnerability occurs during buffer reallocation operations where pointer arithmetic using signed 32-bit integers overflows.

AddressSanitizer:DEADLYSIGNAL
=================================================================
==143838==ERROR: AddressSanitizer: UNKNOWN SIGNAL on unknown address 0x000000000000

References

github.com/ImageMagick/ImageMagick
github.com/ImageMagick/ImageMagick/security/advisories/GHSA-xg29-8ghv-v4xr
github.com/advisories/GHSA-xg29-8ghv-v4xr
github.com/dlemstra/Magick.NET/releases/tag/14.10.3
nvd.nist.gov/vuln/detail/CVE-2026-25970

Code Behaviors & Features

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