How severe is CVE-2026-46521?

CVE-2026-46521 has a CVSS score of 5.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2026-46521?

CVE-2026-46521 affects the following packages: Magick.NET-Q16-AnyCPU (NuGet), Magick.NET-Q16-HDRI-AnyCPU (NuGet), Magick.NET-Q16-HDRI-OpenMP-arm64 (NuGet), Magick.NET-Q16-HDRI-OpenMP-x64 (NuGet), Magick.NET-Q16-HDRI-arm64 (NuGet), Magick.NET-Q16-HDRI-x64 (NuGet), Magick.NET-Q16-HDRI-x86 (NuGet), Magick.NET-Q16-OpenMP-arm64 (NuGet), and 10 more. Ecosystems affected: NuGet.

How do I fix CVE-2026-46521?

Update Magick.NET-Q16-AnyCPU to 14.13.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-46521 is resolved across your whole dependency graph.

How do I detect CVE-2026-46521 in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Magick.NET-Q16-AnyCPU, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-46521 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2026-46521 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-46521 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-46521?

CVE-2026-46521 has an EPSS (Exploit Prediction Scoring System) score of 0.1%, placing it in the 3th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-46521?

CVE-2026-46521 is classified as CWE-131 (CWE-131), CWE-252 (CWE-252), Out-of-bounds Write (CWE-787), CWE-835 (CWE-835). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-46521 published, and has it been updated?

CVE-2026-46521 was published on June 10, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET

.NET NuGet

Not in CISA KEV

MEDIUM severity

CVE-2026-46521 — Magick.NET-Q16-AnyCPU

MEDIUM

CVE-2026-46521 is a medium-severity (CVSS 5.5) CWE-131 vulnerability in Magick.NET-Q16-AnyCPU. A fix is available for Magick.NET-Q16-AnyCPU — see the affected versions and patch details below.

ImageMagick: Heap Buffer Over-Write in MIFF encoder when using LZMA compression

Also known asGHSA-jcqp-6r6f-3mfx

Published

Jun 10, 2026

Updated

Aug 12, 2026

Affected

18 pkgs

Patched

18 / 18

Exploits

None indexed

Exploitation data as of Sep 27, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-46521.

EPSS Exploitation Probability

via FIRST.org ↗

0.1%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs3th percentile — riskier than 3% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2026-46521 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 380,526 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

18 pkgs affected

.NETMagick.NET-Q16-AnyCPU.NETMagick.NET-Q16-HDRI-AnyCPU.NETMagick.NET-Q16-HDRI-OpenMP-arm64.NETMagick.NET-Q16-HDRI-OpenMP-x64.NETMagick.NET-Q16-HDRI-arm64.NETMagick.NET-Q16-HDRI-x64.NETMagick.NET-Q16-HDRI-x86.NETMagick.NET-Q16-OpenMP-arm64+10 more

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

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.

Affected Packages

18 total 18 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`Magick.NET-Q16-AnyCPU`	all versions	14.13.1`dotnet add package Magick.NET-Q16-AnyCPU --version 14.13.1`
.NETNuGet	`Magick.NET-Q16-HDRI-AnyCPU`	all versions	14.13.1`dotnet add package Magick.NET-Q16-HDRI-AnyCPU --version 14.13.1`
.NETNuGet	`Magick.NET-Q16-HDRI-OpenMP-arm64`	all versions	14.13.1`dotnet add package Magick.NET-Q16-HDRI-OpenMP-arm64 --version 14.13.1`
.NETNuGet	`Magick.NET-Q16-HDRI-OpenMP-x64`	all versions	14.13.1`dotnet add package Magick.NET-Q16-HDRI-OpenMP-x64 --version 14.13.1`
.NETNuGet	`Magick.NET-Q16-HDRI-arm64`	all versions	14.13.1`dotnet add package Magick.NET-Q16-HDRI-arm64 --version 14.13.1`
.NETNuGet	`Magick.NET-Q16-HDRI-x64`	all versions	14.13.1`dotnet add package Magick.NET-Q16-HDRI-x64 --version 14.13.1`

Affected Products

1 product · 2 configurations

Application

imagemagickimagemagick

≥ 7.0.0-0 && < 7.1.2-23

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Magick.NET-Q16-AnyCPU, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Magick.NET-Q16-AnyCPU to 14.13.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-46521 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2026-46521 in your dependencies?

Find it across NuGet, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

5.5/10CVSS v3 base

Vector breakdown

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Raw vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CWE Classification

CWE-131CWE-131 CWE-252CWE-252 CWE-787Out-of-bounds Write CWE-835CWE-835

Weaponization

No known public exploit tooling found.

Timeline

Disclosed

Jun 10, 2026

Last updated

Aug 12, 2026

Identifiers

CVE-2026-46521

GHSA-jcqp-6r6f-3mfx

References

Advisorygithub.com Advisorygithub.com Advisorynvd.nist.gov Packagegithub.com

Related vulnerabilities

This CVE is medium severity; 3 of 8 other CVEs affecting Magick.NET-Q16-AnyCPU are rated as high or higher (top: moderate).

GHSA-cvhv-g4rq-3hmwCVE-2026-53466CVE-2026-62363GHSA-56m6-8q75-f2rwGHSA-6jwg-7q3p-5fqmGHSA-6vxp-gfwf-hcr9GHSA-76q6-2p6h-xjqrGHSA-7c7m-fpjw-gwcq

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedAug 12, 2026

CVE-2026-46521 — Magick.NET-Q16-AnyCPU

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2026-46521 in your dependencies?