Microsoft DirectX: .spritefont multiply overflow only in 32-bit builds
Impact
The spritefont reader can be induced to perform a 32-bit overflow multiply that could in theory result in a RCE.
This impacts the use of the DirectX Tool Kit SpriteFont class file loading ctor if given untrusted data files.
Note this only applies to x86/ARM builds of the library. ARM64 and x64 native is not subject to this issue.
Patches
This bug has been fixed in the May 7, 2026 release. Alternatively, users can update their copy of the reader as per this commit.
Workarounds
This does not apply if a project's .spritefont files are all 'trusted' data that were included with an application. It's primarily an issue only if developers are using user-provided or network downloaded spritefont files.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| .NET (NuGet) | directxtk_desktop_win10 | < 2026.5.8.1 | 2026.5.8.1 |
| .NET (NuGet) | directxtk_uwp | < 2026.5.8.1 | 2026.5.8.1 |
References
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N- Weakness (CWE)
CWE-190- Platform
- .NET (NuGet)
- Package
directxtk_desktop_win10, directxtk_uwp- Disclosed
- 18.05.2026
- Updated
- 11.10.2026 11:23
Sources and licenses
OSV / GitHub Advisory Database - GHSA-c55g-rp4x-fx84 - CC BY 4.0
Vulnerability history: directxtk_desktop_win10
All published vulnerabilities of this package (.NET (NuGet)), newest first. Shows whether this is a one-off slip or a package that needs watching.
This is the only known vulnerability of this package.
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