CVE-2026-55577

What it actually does

This vulnerability is a heap buffer overflow in ImageMagick's MVG image decoder. When ImageMagick processes a specially crafted MVG image, the decoder can perform an out-of-bounds write on heap memory. The most likely direct impact is process crash and denial of service in applications, services, batch jobs, or web upload workflows that automatically parse images with ImageMagick. The published CVSS vector indicates network-reachable attack scenarios are possible where image processing is exposed through an application, no privileges or user interaction are required, attack complexity is high, and the scored impact is availability-only. Although heap overflows can sometimes be developed into code execution depending on allocator behavior, build hardening, and process sandboxing, the currently described and scored impact is denial of service.

Why it matters to the business

Organizations using ImageMagick to process untrusted images could experience outages or repeated failures in image upload, conversion, thumbnailing, document rendering, media pipeline, or content moderation services if attackers submit crafted MVG files. This can disrupt customer-facing workflows, delay processing queues, and increase operational load for teams that must restart failed workers or clear poison-pill inputs. The vulnerability is not currently listed in CISA KEV, has no reported ransomware association, and has a low EPSS score of 0.00226, so broad exploitation is not indicated; however, ImageMagick is widely embedded in web applications and backend processing pipelines, so exposure can be easy to overlook.

How an attack unfolds

An attacker first identifies an application or service that accepts user-supplied images or files and processes them with ImageMagick, either directly or through a wrapper library. The attacker crafts an MVG file that triggers the vulnerable decoder path and causes an out-of-bounds heap write during parsing. The file may be uploaded with an MVG extension or disguised using another extension, depending on how the target application validates content and invokes ImageMagick. When the backend conversion, identify, thumbnail, or metadata extraction task processes the file on a vulnerable ImageMagick version prior to 6.9.13-51 or 7.1.2-26, the ImageMagick process can crash. Repeated submissions can create a denial-of-service condition by crashing web workers, conversion daemons, queue consumers, or scheduled image-processing jobs. Successful exploitation depends on reaching the MVG decoder and satisfying heap-layout conditions, which is why the attack complexity is rated high.

How to fix it

Upgrade ImageMagick to a fixed release: version 6.9.13-51 or later for the 6.x branch, or version 7.1.2-26 or later for the 7.x branch. If ImageMagick is supplied by an operating-system package manager, install the vendor security update and verify that the vendor backport includes the MVG decoder fix even if the displayed upstream version appears older. Rebuild or redeploy containers, serverless images, desktop bundles, and application packages that include statically bundled ImageMagick libraries or command-line tools. If immediate upgrading is not possible, reduce exposure by disabling or blocking MVG processing for untrusted input, enforcing strict file type allowlists based on validated magic/content rather than filename extensions, running ImageMagick under a low-privilege account, using resource limits, and sandboxing conversion workers with seccomp/AppArmor/SELinux, containers, or isolated job runners. Review ImageMagick policy.xml to restrict dangerous or unnecessary coders, including MVG if it is not business-critical.

How to confirm the fix worked

Confirm the installed ImageMagick version with commands such as `magick -version`, `convert -version`, or package-manager queries, and ensure it is 6.9.13-51 or later on ImageMagick 6.x, or 7.1.2-26 or later on ImageMagick 7.x, or that the platform vendor has backported the fix. Validate all runtime locations, including containers, build images, CI runners, application bundles, and worker hosts, because multiple ImageMagick copies can coexist. Check ImageMagick policy configuration to confirm MVG is disabled if using mitigation rather than patching. Test representative upload and conversion workflows to verify they still function after upgrade or policy changes. Use software composition analysis, container scanning, and package inventory to identify vulnerable embedded ImageMagick installations. For exposure validation, identify externally reachable workflows that process user-controlled image files or remote URLs and confirm whether they can invoke MVG decoding.

Typical attack path

1. Find an application, API, CMS, processing queue, or backend service that accepts image uploads or remote image URLs.
2. Determine or infer that submitted files are processed by ImageMagick, for example for conversion, resizing, thumbnail generation, or file identification.
3. Prepare a crafted MVG image that exercises the vulnerable MVG decoder heap overflow condition.
4. Submit the crafted file directly or disguise it with another filename extension if the application relies on weak extension-based validation.
5. Wait for the backend ImageMagick workflow to parse the file using a vulnerable version prior to 6.9.13-51 or 7.1.2-26.
6. Cause the ImageMagick process or the dependent worker process to crash, resulting in failed jobs, service degradation, or denial of service.
7. Repeat submissions or place the malicious file into automated processing paths to sustain disruption.

How to detect it

To assess prior exploitation, review logs from applications, APIs, upload services, media-processing workers, job queues, and web servers for MVG file submissions or image-processing failures followed by crashes. Examine ImageMagick stderr/stdout logs, application exception logs, process supervisor logs, container runtime events, kernel logs, and crash reporting systems for segmentation faults, aborts, out-of-bounds write diagnostics, or repeated restarts involving `magick`, `convert`, `identify`, or application workers that link to ImageMagick. Correlate crash times with file uploads, remote image fetches, queue messages, or conversion jobs from the same source IP, user agent, account, or session. Look for files whose content begins with MVG syntax such as `push graphic-context`, `viewbox`, `fill`, `stroke`, or other vector drawing commands, especially when stored with non-MVG extensions. In hardened builds, look for AddressSanitizer, glibc malloc, or kernel messages indicating heap corruption during MVG decoding. Preserve suspicious uploaded files and worker crash dumps for offline analysis in an isolated environment. Because no public exploit maturity or known threat actors are reported in the supplied intelligence, detection should focus on anomalous crashes and crafted-image submissions rather than actor-specific infrastructure.

• MVG
• mvg
• image/x-mvg
• push graphic-context
• pop graphic-context
• viewbox
• fill
• stroke
• convert:
• magick:
• identify:
• Segmentation fault
• segfault
• heap-buffer-overflow
• heap buffer overflow
• out of bounds write
• out-of-bounds write
• malloc(): corrupted top size
• malloc(): invalid size
• double free or corruption
• corrupted double-linked list
• AddressSanitizer: heap-buffer-overflow
• AddressSanitizer: attempting free on address which was not malloc()-ed
• policy.xml
• coder="MVG"
• pattern="MVG"
• magick
• convert
• identify

What your security team should do

• Prioritize patching internet-facing upload, conversion, media processing, CMS, and document-processing services that use ImageMagick on untrusted files.
• Upgrade to ImageMagick 6.9.13-51 or later, or 7.1.2-26 or later, and redeploy all containers and application images that bundle ImageMagick.
• If patching is delayed, disable MVG decoding in ImageMagick policy.xml and enforce strict server-side allowlists for accepted image formats.
• Search asset inventories, container registries, CI/CD images, and application dependencies for bundled ImageMagick copies rather than relying only on OS package inventories.
• Run ImageMagick conversion workers with least privilege, filesystem isolation, resource limits, and process supervision to limit denial-of-service blast radius.
• Add monitoring for abnormal ImageMagick, convert, or magick process crashes, repeated failed image-processing jobs, and suspicious MVG uploads.
• Review upload validation logic to ensure content inspection is used and that extension-only filtering cannot route disguised MVG content into ImageMagick.
• Because the vulnerability is not in CISA KEV and EPSS is low, handle as priority risk for exposed image-processing services rather than as an emergency across all systems.