CVE-2026-53465

What it actually does

ImageMagick versions prior to 7.1.2-25 contain a heap buffer overwrite in the SF3 encoder when processing a crafted multi-frame image. An attacker who can cause a vulnerable ImageMagick installation to encode a malicious image into the SF3 format can corrupt heap memory and trigger a denial of service. Based on the published scoring, the known impact is availability loss rather than confirmed code execution, data theft, or privilege escalation.

Why it matters to the business

Systems that use ImageMagick for automated image conversion, thumbnailing, media ingestion, document processing, or user-upload handling may experience crashes or service disruption if they process a malicious image through the vulnerable SF3 encoding path. The current public exploitation likelihood is low, it is not listed in CISA KEV, and no mature exploit is reported, but ImageMagick is commonly embedded in web applications, CMS platforms, CI pipelines, and backend media services, so organizations should still patch during normal maintenance and prioritize any internet-facing or untrusted-file-processing workloads.

How an attack unfolds

An attacker first identifies an application or workflow that accepts attacker-controlled image files and processes them with ImageMagick. The attacker supplies a specially crafted multi-frame image and causes the application, script, or user workflow to encode that image using ImageMagick's SF3 encoder. During encoding, vulnerable versions before 7.1.2-25 write beyond the bounds of a heap buffer. The most likely observable result is a crash of the ImageMagick process or the parent service invoking it, causing failed image processing jobs or temporary service unavailability. There is no public indication that this vulnerability is currently exploited in the wild, used by ransomware campaigns, or associated with named threat actors.

How to fix it

Upgrade ImageMagick to version 7.1.2-25 or later. Where ImageMagick is provided by an operating system or container distribution, install the vendor-supplied patched package even if the displayed upstream version differs. Rebuild containers, serverless images, application bundles, and static deployments that include vulnerable ImageMagick libraries or binaries. If immediate patching is not possible, disable or restrict SF3 encoding, block conversion to SF3 in application-level allowlists, avoid processing untrusted multi-frame images, and run ImageMagick in a sandbox with resource limits, least privilege, and process isolation.

How to confirm the fix worked

Confirm the installed ImageMagick version with `magick -version` or `convert -version` and verify it reports 7.1.2-25 or a vendor-backported fixed build. Check container images, application dependencies, CI runners, media-processing workers, and packaged appliances for embedded ImageMagick binaries. Validate that applications do not permit untrusted users to request SF3 output unless the patched version is deployed. For mitigations, test that SF3 encoding is blocked or that ImageMagick policy configuration prevents the vulnerable workflow. Review package manager metadata, software composition analysis results, and runtime inventories to ensure no older ImageMagick binaries remain in active paths.

Typical attack path

1. Locate an application, batch job, or service that uses ImageMagick to process untrusted images.
2. Submit or place a crafted multi-frame image where the vulnerable workflow will process it.
3. Trigger conversion or encoding into the SF3 format using ImageMagick before version 7.1.2-25.
4. Cause heap memory corruption in the SF3 encoder.
5. Crash the ImageMagick process or disrupt the dependent application or processing pipeline.

How to detect it

Look for evidence of attempted or successful exploitation in application logs, media-processing worker logs, job queue failures, crash dumps, container restart events, and system logs around ImageMagick invocations. Focus on workflows that encode images to SF3, process multi-frame images, or accept untrusted uploads. Indicators include repeated crashes of `magick`, `convert`, or application workers immediately after file conversion; error messages mentioning SF3; kernel or service-manager logs showing segmentation faults; sanitizer reports showing heap-buffer-overflow; and sudden spikes in failed image conversion jobs. If file upload logging is available, correlate suspicious multi-frame image uploads with subsequent ImageMagick crashes. Preserve uploaded samples, temporary conversion files, core dumps, command-line arguments, and parent process logs for forensic review.

• coders/sf3
• SF3
• heap-buffer-overflow
• heap buffer overflow
• heap-buffer-overwrite
• heap buffer overwrite
• AddressSanitizer
• runtime error: index out of bounds
• Segmentation fault
• segfault at
• core dumped
• magick
• convert
• identify
• mogrify
• MagickCore
• MagickWand
• .sf3

What your security team should do

• Inventory all uses of ImageMagick, including containers, web upload handlers, media-processing queues, CI/CD jobs, CMS plugins, and document-conversion services.
• Patch ImageMagick to 7.1.2-25 or later, prioritizing systems that process untrusted or internet-supplied files.
• If patching is delayed, disable SF3 encoding and restrict allowed output formats to those required by the business.
• Run ImageMagick workloads with sandboxing, memory and CPU limits, non-root privileges, and file-system isolation.
• Add monitoring for repeated ImageMagick crashes, failed conversion jobs, and application errors involving SF3 or multi-frame image processing.
• Rebuild and redeploy base images or application artifacts that statically bundle ImageMagick rather than relying only on host package updates.