Improper certificate validation in Visual Studio allows an unauthorized attacker to perform spoofing over a network.
Summary
Out-of-bounds Write vulnerability in the bundled Brotli decoder in yjh0502 erl-brotli allows an attacker who supplies a crafted Brotli-compressed stream to brotli:decode/1 to corrupt decoder state memory, disclose memory contents, crash the Erlang VM, or potentially execute code.
erl-brotli compiles its own copy of the Google Brotli C sources under csrc into a NIF, and brotlidecoderdecompressstream in csrc/brotlinif.c hands the input to BrotliDecoderDecompressStream. In csrc/dec/decode.c, DecodeBlockTypeAndLength returns false for a block switch in a category with at most one block type, and the non-streaming callers DecodeLiteralBlockSwitch, DecodeCommandBlockSwitch and DecodeDistanceBlockSwitch discard that result, so decoding continues with inconsistent state. The decoder runs inside a NIF, so memory corruption or a crash takes down the whole VM rather than the calling process. Because the package carries its own copy of the library, the Brotli version installed on the host does not matter.
This issue affects brotli: from 0.3.0 before 0.3.4.
Impact
An attacker who can get an application to decode a Brotli stream they control, for example an HTTP client that decompresses Content-Encoding: br responses with this package, can crash the Erlang VM and potentially run code inside it.
.NET and Visual Studio Remote Code Execution Vulnerability
Executive summary
Microsoft is releasing this security advisory to provide information about a vulnerability in the Blazor WebAssembly debugger included in Microsoft.AspNetCore.Components.WebAssembly.Server. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
The Blazor WebAssembly debug proxy evaluates debugger expressions by generating and compiling C# source. Certain values originating in the application being debugged, including ToString() results, descriptions, and class names, are embedded in that generated source without consistent escaping. An attacker-controlled value can escape the generated string literal and execute code on a developer's machine when the developer evaluates an expression during debugging.
Announcement
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/445
CVSS Details
- Version: 3.1 - Severity: High - Score: 8.8 - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness: CWE-94 (Improper Control of Generation of Code ('Code Injection'))
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 ------------ | ---------------- | --------------- Microsoft.AspNetCore.Components.WebAssembly.Server | >= 10.0.0, <= 10.0.12 | 10.0.13 Microsoft.AspNetCore.Components.WebAssembly.Server | >= 11.0.0-preview.1, <= 11.0.0-rc.1 | 11.0.0-rc.2.26478.115
Advisory FAQ
<a name="how-affected"></a>How do I know if I am affected?
You are affected if you use a vulnerable version of Microsoft.AspNetCore.Components.WebAssembly.Server to debug a Blazor WebAssembly application and evaluate an expression involving attacker-controlled application data.
<a name="how-fix"></a>How do I fix the issue?
1. Install the latest supported version of .NET. 2. Update Microsoft.AspNetCore.Components.WebAssembly.Server to the patched version for the .NET release used by the application.
Once the updated package or runtime is installed, restart the debugger and development environment.
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 repositories are located at https://github.com/dotnet/runtime and https://github.com/dotnet/aspnetcore. The Announcements repository (https://github.com/dotnet/announcements) will contain this bulletin as an issue and will include a link to a 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-2026-102870
Acknowledgements
alittleston3
Revisions
V1.0 (10/13/2026): Advisory published.
.NET Security Feature Bypass Vulnerability
Improper access control in Visual Studio allows an authorized attacker to elevate privileges locally.
Improper link resolution before file access ('link following') in Visual Studio allows an unauthorized attacker to elevate privileges over a network.
CVE-2025-48384 is regarding a vulnerability in Git where when reading a config value, Git strips any trailing carriage return and line feed (CRLF). When writing a config entry, values with a trailing CR are not quoted, causing the CR to be lost when the config is later read. When initializing a submodule, if the submodule path contains a trailing CR, the altered path is read resulting in the submodule being checked out to an incorrect location. If a symlink exists that points the altered path to the submodule hooks directory, and the submodule contains an executable post-checkout hook, the script may be unintentionally executed after checkout. GitHub created this CVE on their behalf. The documented Visual Studio updates incorporate updates in Git which address this vulnerability. Please see CVE-2025-48384 for more information.
Improper neutralization of special elements used in a command ('command injection') in Visual Studio allows an unauthorized attacker to execute code locally.
Insufficient granularity of access control in Visual Studio allows an authorized attacker to disclose information locally.
Uncontrolled search path element in Visual Studio allows an authorized attacker to elevate privileges locally.
Uncontrolled search path element in Visual Studio allows an authorized attacker to elevate privileges locally.
Visual Studio Installer Elevation of Privilege Vulnerability
Visual Studio Remote Code Execution Vulnerability
.NET and Visual Studio Remote Code Execution Vulnerability
Description The Git credential protocol is text-based over standard input/output, and consists of a series of lines of key-value pairs in the format key=value. Git's documentation restricts the use of the NUL (\0) character and newlines to form part of the keys[^1] or values.
When Git reads from standard input, it considers both LF and CRLF[^2] as newline characters for the credential protocol by virtue of calling strbufgetline that calls to strbufgetdelimstripcrlf. Git also validates that a newline is not present in the value by checking for the presence of the line-feed character (LF, \n), and errors if this is the case. This captures both LF and CRLF-type newlines.
Git Credential Manager uses the .NET standard library StreamReader class to read the standard input stream line-by-line and parse the key=value credential protocol format. The implementation of the ReadLineAsync method considers LF, CRLF, and CR as valid line endings. This is means that .NET considers a single CR as a valid newline character, whereas Git does not.
This mismatch of newline treatment between Git and GCM means that an attacker can craft a malicious remote URL such as:
https://\rhost=targethost@badhost
..which will be interpreted by Git as:
protocol=https host=badhost username=\rhost=targethost
This will instead be parsed by GCM as if the following has been passed by Git:
protocol=https host=badhost username= host=targethost
This results in the host field being resolved to the targethost value. GCM will then return a credential for targethost to Git, which will then send this credential to the badhost host.
Impact When a user clones or otherwise interacts[^3] with a malicious repository that requires authentication, the attacker can capture credentials for another Git remote. The attack is also heightened when cloning from repositories with submodules when using the --recursive clone option as the user is not able to inspect the submodule remote URLs beforehand.
Patches https://github.com/git-ecosystem/git-credential-manager/compare/749e287571c78a2b61f926ccce6a707050871ab8...99e2f7f60e7364fe807e7925f361a81f3c47bd1b
Workarounds Only interacting with trusted remote repositories, and do not clone with --recursive to allow inspection of any submodule URLs before cloning those submodules.
Fixed versions This issue is fixed as of version 2.6.1.
[^1]: The = character is also forbidden to form part of the key. [^2]: Carriage-return character (CR, \r), followed by a line-feed character. [^3]: Any remote operation such as fetch, ls-remote, etc.
Visual Studio Collector Service Denial of Service Vulnerability
Visual C++ Redistributable Installer Elevation of Privilege Vulnerability
Visual Studio Remote Code Execution Vulnerability
Visual Studio Elevation of Privilege Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability