CVE-2026-45664

What it actually does

ImageMagick before 6.9.13-47 and 7.1.2-22 has a missing enforcement check in the MNG image decoder. A crafted or unusually structured MNG file can cause ImageMagick to process more embedded images/frames than the configured list-limit policy should allow. This can drive excessive CPU, memory, disk, or worker-process consumption and cause partial denial of service in applications, background jobs, upload pipelines, thumbnailers, or content-processing services that automatically invoke ImageMagick on untrusted image input.

Why it matters to the business

Organizations that accept or process user-supplied images may experience degraded service, failed image processing, queue backlogs, increased infrastructure costs, or temporary unavailability of features that rely on ImageMagick. The issue is not currently listed in CISA KEV, has low EPSS, and has no reported exploit maturity in the provided data, but it is remotely reachable in common upload/processing workflows and should be remediated during normal patch cycles, with higher urgency for internet-facing or high-volume media processing services.

How an attack unfolds

An attacker identifies an application, API, email gateway, document converter, CMS, or media-processing workflow that passes uploaded or fetched image files to ImageMagick. The attacker submits a malicious MNG image designed to make the MNG coder process more images than policy limits intend to permit. When ImageMagick parses the file, the missing policy enforcement allows excessive resource use. Repeated submissions or concurrent requests can exhaust worker capacity, memory, CPU, temporary storage, or job queue throughput, resulting in slowed processing or denial of service for legitimate users. The attack does not require authentication or user interaction when the target service automatically processes attacker-controlled image content.

How to fix it

Upgrade ImageMagick to a patched release: 6.9.13-47 or later for the 6.x branch, or 7.1.2-22 or later for the 7.x branch. Update operating-system packages, container images, application bundles, language package wrappers, and statically packaged ImageMagick binaries that may include vulnerable versions. If immediate upgrade is not possible, reduce exposure by disabling MNG decoding where not required, rejecting or quarantining MNG uploads, enforcing strict file size and frame-count limits at the application layer, setting conservative ImageMagick resource policies for memory/map/disk/time/list limits, processing untrusted files in isolated sandboxes with cgroup/container resource limits, and rate-limiting image-processing requests.

How to confirm the fix worked

Confirm all ImageMagick executables and libraries in use report patched versions by checking `magick -version`, `convert -version`, package manager inventory, and container image SBOMs. Validate that applications use the patched binary or library at runtime, not an older bundled copy. Review policy.xml to ensure resource limits are still enforced and appropriate for the workload. Test that MNG files are either blocked if unsupported or processed within expected resource bounds. For internet-facing upload paths, verify file-type allowlists, request size limits, rate limits, and job timeout controls are active.

Typical attack path

1. Find an externally reachable feature or service that accepts, fetches, or converts image files.
2. Confirm that uploaded or retrieved images are processed by ImageMagick, directly or through a dependent framework or service.
3. Submit a crafted MNG file that causes the decoder to process more image entries than the configured list-limit policy should allow.
4. Repeat or parallelize submissions to amplify CPU, memory, temporary-file, or queue consumption.
5. Cause image-processing workers, background jobs, or dependent application functionality to slow down, fail, restart, or become unavailable.

How to detect it

To assess prior exploitation, review application upload logs, API gateway logs, object-storage access logs, job queue records, image-processing service logs, EDR telemetry, and system resource metrics for periods of abnormal ImageMagick CPU, memory, disk, or runtime consumption. Look for repeated or concurrent processing of MNG files, especially from the same source addresses, accounts, user agents, or unauthenticated upload paths, followed by worker timeouts, process kills, out-of-memory events, container restarts, queue backlogs, or failed conversions. On Linux systems, inspect syslog/journald, kernel OOM logs, container runtime events, and process accounting for `magick`, `convert`, `identify`, or application worker processes terminated during image parsing. Because no public exploit-specific payload signature is provided, detection should focus on behavioral evidence: suspicious MNG submissions correlated with resource exhaustion and service degradation.

• .mng
• image/x-mng
• magick
• convert
• identify
• coders/mng
• MNG
• Out of memory: Kill process
• Killed process
• oom-kill
• memory cgroup out of memory
• Resource temporarily unavailable
• cache resources exhausted
• time limit exceeded
• width or height exceeds limit
• list length exceeds limit

What your security team should do

• Inventory all systems, containers, build images, and applications that invoke ImageMagick or ImageMagick-backed libraries for image conversion, thumbnailing, document processing, or media ingestion.
• Prioritize patching internet-facing upload services, automated file-processing pipelines, shared multi-tenant processing workers, and high-volume media services to ImageMagick 6.9.13-47+/7.1.2-22+.
• Temporarily block or quarantine MNG files if the format is not business-critical.
• Enforce defense-in-depth resource controls: ImageMagick policy.xml limits, worker job timeouts, memory and CPU cgroup limits, upload size caps, concurrency limits, and rate limiting.
• Monitor for abnormal spikes in ImageMagick process runtime, memory use, crashes, queue depth, retry volume, and failed image conversions following uploads of MNG files.
• Rebuild and redeploy containers or application packages that bundle ImageMagick rather than relying only on host package updates.