Summary On Windows builds, Pillow stores EMF and WMF image dimensions without a range check and passes them to the native drawwmf handler. That code sizes its allocation from dimensions truncated into 16-bit header fields but copies the result using the full 32-bit dimensions. A crafted metafile that is wide and short passes the decompression-bomb pixel check yet causes a heap over-read.
Details The EMF branch computes the size straight from signed 32-bit header fields and stores it with no positivity or range check:
- src/PIL/WmfImagePlugin.py:121-129 reads the bounding box; :148 stores it; the size reaches the native handler through src/PIL/WmfImagePlugin.py:56.
In the native handler the DIB header fields bcWidth and bcHeight are 16-bit and truncate the allocation, while the copy length uses the untruncated ints:
- src/display.c:793-794 assign the 16-bit fields - src/display.c:800 sizes the allocation from them - src/display.c:827 copies height ((width 3 + 3) & -4) bytes using the full values
The whole handler is compiled only on Windows (#ifdef WIN32, src/display.c:33-841).
PoC python import struct from PIL import Image
def L(v): return struct.pack("<i", v)
Minimal EMF header. Bounding box is 70000 x 1, so the pixel count (70000) passes the decompression-bomb check, but the width truncates to 16 bits for the allocation while the copy uses 70000. emf = b"\x01\x00\x00\x00" + L(88) # record type + size emf += L(0) + L(0) + L(70000) + L(1) # rclBounds: x0, y0, x1, y1 emf += L(0) + L(0) + L(100) + L(100) # rclFrame (non-zero, used for the dpi calc) emf += b" EMF" # signature at offset 40 emf += bytes(44) open("poc.emf", "wb").write(emf)
im = Image.open("poc.emf") print("size:", im.size, "pixels:", im.size[0] im.size[1]) im.load() # over-read happens here on a Windows build
On Linux the first part is observable: the 88-byte file opens, size is (70000, 1), and the bomb check passes. The native over-read only exists on Windows because Image.core.drawwmf is compiled out elsewhere (on Linux im.load() raises OSError instead).
Impact CWE-125, out-of-bounds read in a C extension on Windows builds. A crafted EMF or WMF that passes the pixel check can read past a heap buffer, leaking memory or crashing the process.
A local privilege escalation vulnerability in the Palo Alto Networks GlobalProtect™ app enables a local user to escalate their privileges to root on macOS. This enables a non-administrative user to execute arbitrary commands with administrative privileges.
The GlobalProtect app on Linux, Windows, iOS, Android and Chrome OS is not affected by this vulnerability.
Substance3D - Designer is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Photoshop Desktop is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Photoshop Desktop is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Photoshop Desktop is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Photoshop Desktop is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Photoshop Desktop is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Photoshop Desktop is affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Photoshop Desktop is affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
Heap-based buffer overflow in Windows Virtualization-Based Security (VBS) Enclave allows an authorized attacker to elevate privileges locally.
Microsoft Windows PDF Remote Code Execution Vulnerability
.NET Denial of Service Vulnerability
.NET Security Feature Bypass Vulnerability
.NET Denial of Service Vulnerability
.NET Denial of Service Vulnerability
Executive summary
Microsoft is releasing this security advisory to provide information about a vulnerability in System.Security.Cryptography.Xml. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
KeyInfoX509Data can accept serialized certificate formats containing attacker-controlled chain metadata instead of requiring a plain X.509 certificate, contributing to certificate-forgery and token-spoofing paths.
Announcement
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/474
CVSS Details
- Version: 3.1 - Severity: High - Score: 7.4 - Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - Weakness: CWE-295 (Improper Certificate Validation)
Affected Platforms
- Platforms: Windows, Linux, macOS - Architectures: All
<a name="affected-packages"></a>Affected Packages
The vulnerability affects Microsoft .NET projects that use an affected package version listed below.
Package name | Affected version | Patched version ------------ | ---------------- | --------------- System.Security.Cryptography.Xml | >= 8.0.0, <= 8.0.4 | 8.0.5
Advisory FAQ
<a name="how-affected"></a>How do I know if I am affected?
If using a package listed in affected packages, you're exposed to the vulnerability.
<a name="how-fix"></a>How do I fix the issue?
1. To fix the issue please install the latest version of .NET. If you have installed one or more .NET SDKs through Visual Studio, Visual Studio will prompt you to update Visual Studio, which will also update your .NET SDKs. 2. If your application references the vulnerable package, update the package reference to the patched version. You can list the versions you have installed by running the dotnet --info command.
Once you have installed the updated runtime or SDK, restart your apps for the update to take effect.
Additionally, if you've deployed self-contained applications targeting any of the impacted versions, these applications are also vulnerable and must be recompiled and redeployed.
Other Information
Reporting Security Issues
If you have found a potential security issue in a supported version of .NET, please report it to the Microsoft Security Response Center (MSRC) via the MSRC Researcher Portal. Further information can be found in the MSRC Report an Issue FAQ.
Security reports made through MSRC may qualify for the Microsoft .NET Bounty. Details of the Microsoft .NET Bounty Program including terms and conditions are at https://aka.ms/corebounty.
Support
You can ask questions about this issue on GitHub in the .NET GitHub organization. The main repos are located at https://github.com/dotnet/runtime. The Announcements repo (https://github.com/dotnet/Announcements) will contain this bulletin as an issue and will include a link to a discussion issue. You can ask questions in the linked discussion issue.
Disclaimer
The information provided in this advisory is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
External Links
CVE-2026-96222
Acknowledgements
- Vaisha Bernard with Eye Security
Revisions
V1.0 (10/13/2026): Advisory published.
Improper neutralization of special elements used in a command ('command injection') in Windows Shell allows an unauthorized attacker to bypass a security feature over a network.
When rendering the page image, Foxit PDF Editor/Reader fails to perform validation on image objects whose optional content attributes are malformed. As a result, the program may access an already-freed internal data structure, triggering a crash due to UAF.
When processing a specially crafted PDF file, Foxit PDF Editor/Reader may encounter a reentrant execution condition involving JavaScript triggered by page-visibility events. This can cause the application to access a released page-view object while calculating annotation boundaries, resulting in an invalid memory read and application crash.
When processing a specially crafted PDF, Foxit PDF Editor/Reader may perform reentrant zoom and layout operations through page- and annotation-related JavaScript actions. This can cause the application to access page objects after they have been released, resulting in a use-after-free condition and an application crash.
When opening a specially crafted PDF, Foxit PDF Editor/Reader executes scripts that modify annotation rich-text attributes containing malformed font data. During subsequent annotation appearance reconstruction, it accesses an object after it has been released, resulting in a use-after-free condition and an application crash.
Foxit PDF Editor/Reader's FileOpen plugin did not adequately validate certain encryption metadata in specially crafted PDF files. This could leave an internal pointer in an invalid state, resulting in chained read and write access violations and potentially enabling arbitrary code execution.
Foxit PDF Editor/Reader failed to validate the directory traversal path in the attachment file name, resulting in malicious attachments being able to be written to directories outside the expected secure area when the PDF is opened.
A use-after-free vulnerability exists in Foxit PDF Editor/Reader’s handling of JavaScript array objects. A specially crafted PDF may cause the application to access a released object during array processing, potentially resulting in application crashes or arbitrary code execution.
A use-after-free vulnerability exists in Foxit PDF Editor/Reader’s PDF page-tree handling. A specially crafted PDF can trigger page-structure changes during rendering, causing the application to access released page objects and resulting in memory corruption and an application crash.
A path traversal vulnerability exists in Foxit PDF Editor/Reader's handling of embedded PDF resources. Insufficient validation of resource file paths may allow files to be written outside their intended locations, potentially enabling arbitrary code execution.
A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s WebP image decoding due to improper handling of bitmap stride and target buffer formats. Successful exploitation could result in an application crash.
A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s rendering of Circle annotations with malformed Cloudy appearance streams in specially crafted PDF files. Insufficient validation of the appearance geometry can result in memory corruption and application crashes.
A use-after-free vulnerability exists in Foxit PDF Editor/Reader’s handling of PDF form fields. Embedded JavaScript may access form-field references after the corresponding fields have been released, resulting in an application crash.