GHSA-5r97-79vw-qvm4 Microsoft DirectX12: .spritefont multiply overflow only in 32-bit builds
An integer overflow in the SpriteFont reader allows remote code execution when processing untrusted data files in 32-bit builds.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Not stated
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is GHSA-5r97-79vw-qvm4?
GHSA-5r97-79vw-qvm4 is a vulnerability in directxtk12_desktop_win10, published on 18 May 2026.
Official description
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, you can just update your 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.
Which versions are affected by GHSA-5r97-79vw-qvm4?
4 open source packages ship an affected version, including directxtk12_desktop_win10 and directxtk12_uwp.
| Package | Affected | Fixed in |
|---|---|---|
directxtk12_desktop_win10 NuGet | All versions | 2026.5.8.1 |
directxtk12_desktop_win10 NuGet | All versions | 2026.5.8.1 |
directxtk12_uwp NuGet | All versions | 2026.5.8.1 |
directxtk12_uwp NuGet | All versions | 2026.5.8.1 |
How do I fix GHSA-5r97-79vw-qvm4?
Upgrade directxtk12_desktop_win10 to 2026.5.8.1 or later.
Is GHSA-5r97-79vw-qvm4 being exploited?
There is no known exploitation of GHSA-5r97-79vw-qvm4 in the wild and no public exploit code.