CVE-2025-57807

What it actually does

SeekBlob on memory-backed BlobStream advances offset past current extent without resizing; subsequent WriteBlob then reallocates by quantum+length and performs copy at data+offset, resulting in deterministic out-of-bounds heap write on 64-bit builds.

Why it matters to the business

Applications that process images with ImageMagick may experience crashes, memory corruption, or remote code execution, leading to service outages, data integrity issues, or full system compromise when handling untrusted inputs.

How an attack unfolds

An attacker supplies input that causes an ImageMagick blob operation to invoke SeekBlob with an offset larger than the current allocation, followed by WriteBlob that expands insufficiently and writes attacker-controlled data past the heap buffer end.

How to fix it

Upgrade imagemagick/imagemagick to commit 077a417a19a5ea8c85559b602754a5b928eef23e or later; rebuild dependent packages and restart services that link against the library.

How to confirm the fix worked

Confirm installed version contains commit 077a417a19a5ea8c85559b602754a5b928eef23e; run regression tests with crafted blob seek/write sequences; monitor for heap-related crashes or sanitizer violations during image operations.

Typical attack path

1. Trigger ImageMagick code path that creates a memory-backed BlobStream
2. Call SeekBlob to advance offset beyond current extent
3. Invoke WriteBlob with data that forces reallocation and out-of-bounds copy
4. Achieve deterministic heap write to corrupt adjacent structures or gain control flow

How to detect it

Monitor ImageMagick processes for segmentation faults or heap corruption signals in system logs; inspect application error logs for blob-related failures; review crash dumps for out-of-bounds write patterns near blob allocation routines.

What your security team should do

• Immediately update all ImageMagick installations to the fixed commit
• Scan build pipelines and containers for older ImageMagick versions
• Add memory sanitizer or ASAN checks to CI for image-processing workloads
• Review and restrict ImageMagick usage on untrusted inputs where possible