# CVE-2026-46521: ImageMagick: Heap Buffer Over-Write in MIFF encoder when using LZMA compression > Attackers can trigger heap buffer overwrites in ImageMagick's MIFF encoder with LZMA compression, potentially leading to code execution or crashes. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Local or same network only - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 10 Jun 2026 - **Updated:** 11 Jun 2026 - **Also known as:** DEBIAN-CVE-2026-46521, ECHO-3d1a-d16a-7322, GHSA-jcqp-6r6f-3mfx, JLSEC-2026-1013, MINI-6g22-g68p-2qv3, UBUNTU-CVE-2026-46521 ## What is CVE-2026-46521? CVE-2026-46521 is a medium-severity memory corruption vulnerability in Imagemagick Imagemagick, published on 10 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. ### Official description ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to versions 6.9.13-48 and 7.1.2-23, when using LZMA compression in the MIFF encoder an out of bounds write can occur due to a missing check. This issue has been patched in versions 6.9.13-48 and 7.1.2-23. Weakness: CWE-835 (Loop with Unreachable Exit Condition), CWE-787 (Out-of-bounds Write), CWE-252 (Unchecked Return Value), CWE-131 (Incorrect Calculation of Buffer Size) ## Which versions are affected by CVE-2026-46521? 36 open source packages ship an affected version, including Magick.NET-Q16-AnyCPU, Magick.NET-Q16-HDRI-AnyCPU and Magick.NET-Q16-HDRI-OpenMP-arm64. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `Magick.NET-Q16-AnyCPU` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-AnyCPU` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-AnyCPU` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-AnyCPU` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-OpenMP-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-OpenMP-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-OpenMP-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-OpenMP-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-x86` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-HDRI-x86` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-OpenMP-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-OpenMP-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-OpenMP-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-OpenMP-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-x86` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q16-x86` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-AnyCPU` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-AnyCPU` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-OpenMP-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-OpenMP-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-OpenMP-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-OpenMP-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-arm64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-x64` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-x86` | NuGet | All versions | 14.13.1 | | `Magick.NET-Q8-x86` | NuGet | All versions | 14.13.1 | Products: Imagemagick Imagemagick. ## How do I fix CVE-2026-46521? Upgrade Magick.NET-Q16-AnyCPU to 14.13.1 or later. ## Is CVE-2026-46521 being exploited? There is no known exploitation of CVE-2026-46521 in the wild and no public exploit code. ## Other vulnerabilities in Imagemagick Imagemagick - [CVE-2019-19952](https://insights.sbomify.com/CVE-2019-19952/): Use after free in n/a (critical 9.8) - [CVE-2018-16328](https://insights.sbomify.com/CVE-2018-16328/): Null dereference in n/a (critical 9.8) - [CVE-2018-16329](https://insights.sbomify.com/CVE-2018-16329/): Null dereference in n/a (critical 9.8) - [CVE-2017-18210](https://insights.sbomify.com/CVE-2017-18210/): Null dereference in n/a (critical 9.8) - [CVE-2017-14138](https://insights.sbomify.com/CVE-2017-14138/): Denial of service in n/a (critical 9.8) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-46521 and fix it if it is affected. What it is: CVE-2026-46521 is a medium-severity memory corruption vulnerability in Imagemagick Imagemagick, published on 10 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2026-46521 in the wild and no public exploit code. Affected packages and fixed versions: - Magick.NET-Q16-AnyCPU (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-AnyCPU (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-AnyCPU (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-AnyCPU (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-OpenMP-x64 (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-OpenMP-x64 (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-arm64 (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-arm64 (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-x64 (NuGet): affected all versions; fixed in 14.13.1 - Magick.NET-Q16-HDRI-x64 (NuGet): affected all versions; fixed in 14.13.1 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-46521/ (Markdown: https://insights.sbomify.com/CVE-2026-46521/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46521 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46521 - OSV: https://osv.dev/vulnerability/CVE-2026-46521 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-46521/ Summaries are generated and may contain mistakes; the official description above is the record.