Executive summary

Microsoft is releasing this security advisory to provide information about a vulnerability in ASP.NET Core. This advisory provides guidance on updating affected applications and components.

SignalR connections are not consistently bound to the identity negotiated at connection establishment, allowing injected messages to execute Hub invocations as the victim.

Announcement

Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/504

CVSS Details

- Version: 3.1 - Severity: Critical - Score: 9.0 (base score) - Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C - Weakness: CWE-863

Affected Platforms

- Platforms: Windows, Linux, macOS - Architectures: All

<a name="affected-packages"></a>Affected Packages

The tables list affected version ranges and fixed package versions. Runtime and standalone deliveries are listed separately.

ASP.NET Core 2.3 - standalone packages

Package | Affected version | Patched version --- | --- | --- Microsoft.AspNetCore.Http.Connections | >= 1.2.0, <= 1.2.13 | 1.2.14

.NET 8.0 - affected runtime packages

Package | Affected version | Patched version --- | --- | --- Microsoft.AspNetCore.App.Runtime.linux-arm | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.linux-arm64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.linux-musl-arm | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.linux-musl-x64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.linux-x64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.osx-arm64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.osx-x64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.win-arm64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.win-x64 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34 Microsoft.AspNetCore.App.Runtime.win-x86 | >= 8.0.0-preview.1.23112.2, <= 8.0.33 | 8.0.34

.NET 9.0 - affected runtime packages

Package | Affected version | Patched version --- | --- | --- Microsoft.AspNetCore.App.Runtime.linux-arm | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.linux-arm64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.linux-musl-arm | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.linux-musl-x64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.linux-x64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.osx-arm64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.osx-x64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.win-arm64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.win-x64 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23 Microsoft.AspNetCore.App.Runtime.win-x86 | >= 9.0.0-preview.1.24081.5, <= 9.0.22 | 9.0.23

.NET 10.0 - affected runtime packages

Package | Affected version | Patched version --- | --- | --- Microsoft.AspNetCore.App.Runtime.linux-arm | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.linux-arm64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.linux-musl-arm | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.linux-musl-x64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.linux-x64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.osx-arm64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.osx-x64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.win-arm64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.win-x64 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15 Microsoft.AspNetCore.App.Runtime.win-x86 | >= 10.0.0-preview.1.25120.3, <= 10.0.14 | 10.0.15

.NET 11.0 - affected runtime packages

Package | Affected version | Patched version --- | --- | --- Microsoft.AspNetCore.App.Runtime.linux-arm | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.linux-arm64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.linux-musl-arm | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.linux-musl-x64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.linux-x64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.osx-arm64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.osx-x64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.win-arm64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.win-x64 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0 Microsoft.AspNetCore.App.Runtime.win-x86 | >= 11.0.0-preview.1.26104.118, <= 11.0.0-rc.3.26522.148 | 11.0.0

Advisory FAQ

<a name="how-affected"></a>How do I know if I am affected?

Check the deployed runtime and application package versions against the affected ranges above. Self-contained applications include their own runtime; updating a machine-wide runtime does not replace it.

<a name="how-fix"></a>How do I fix the issue?

Install the applicable runtime or update each independently referenced package to the fixed version above. After updating standalone packages, rebuild and redeploy affected applications, including framework-dependent applications; restarting alone does not replace app-local packages. Restart applications. Rebuild and redeploy self-contained applications; updating a machine-wide runtime does not replace their embedded runtime. An SDK update alone does not update an application's standalone package references.

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-2026-114146

Acknowledgements

- Mika Vehns with MIVE GmbH - Lucas Gabriel - hsuan0223x - Mariusz Maik - Pocas (Jeongwon Jo) - Grace Chapel - Jacob Keith with Keith Systems - Weeraphat Srisutham - Kevin Gosse - Artur Stetsko - Yudai Shibata - 71C4 - Attila Csatadi of ZeroDayBugs.com - Vu Van Tien ( @n0Be3r )

Revisions

V1.0 (November 10, 2026): Advisory published.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

A use-after-free issue was addressed with improved memory management. This issue is fixed in iOS 26.7.2 and iPadOS 26.7.2, iOS 27.2 and iPadOS 27.2, macOS Golden Gate 27.2, macOS Sequoia 15.8.2, macOS Tahoe 26.7.2, tvOS 27.2, visionOS 27.2, watchOS 27.2. An attacker may be able to cause unexpected system termination or corrupt kernel memory.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27.2, macOS Sequoia 15.8.2, macOS Tahoe 26.7.2. A sandboxed process may be able to circumvent sandbox restrictions.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27.2, macOS Sequoia 15.8.2, macOS Tahoe 26.7.2. A remote attacker may be able to cause unexpected app termination.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

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.

Adobe Connect is affected by an Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') vulnerability that could result in arbitrary code execution in the context of the current user. A low-privileged attacker could exploit this vulnerability to execute arbitrary SQL commands, potentially gaining elevated access or control over the victim's account or session. Exploitation of this issue does not require user interaction. Scope is changed.

Adobe Connect is affected by an Improper Input Validation vulnerability that could result in arbitrary code execution in the context of the current user. An attacker could exploit this vulnerability to execute arbitrary code. Exploitation of this issue requires user interaction in that a victim must visit a maliciously crafted URL or interact with a compromised web page. Scope is changed.

Adobe Connect is affected by a stored Cross-Site Scripting (XSS) vulnerability that could be abused by an attacker to inject malicious scripts into vulnerable form fields. Malicious JavaScript may be executed in a victim's browser when they browse to the page containing the vulnerable field, potentially gaining elevated access or control over the victim's account or session. Scope is changed.

Adobe Connect is affected by a stored Cross-Site Scripting (XSS) vulnerability that could be abused by an attacker to inject malicious scripts into vulnerable form fields. Malicious JavaScript may be executed in a victim's browser when they browse to the page containing the vulnerable field, potentially gaining elevated access or control over the victim's account or session. Scope is changed.

Adobe Connect is affected by a stored Cross-Site Scripting (XSS) vulnerability that could be abused by an attacker to inject malicious scripts into vulnerable form fields. Malicious JavaScript may be executed in a victim's browser when they browse to the page containing the vulnerable field, potentially gaining elevated access or control over the victim's account or session. Scope is changed.

Adobe Connect is affected by a reflected Cross-Site Scripting (XSS) vulnerability. An attacker could exploit this vulnerability to inject malicious scripts into a web page, potentially gaining elevated access or control over the victim's account or session. Exploitation of this issue requires user interaction in that a victim must visit a maliciously crafted URL or interact with a compromised web page. Scope is changed.

A certificate validation issue was addressed with improved certificate validation. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, watchOS 27. An attacker with a compromised intermediate certificate authority may be able to issue certificates with arbitrary extended key usages.

A permissions issue was addressed with improved path validation. This issue is fixed in iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, watchOS 27. An app may be able to modify protected system files.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

A double free issue was addressed with improved memory management. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, watchOS 27. An app may be able to cause unexpected system termination or corrupt kernel memory.

A permissions issue was addressed with additional sandbox restrictions. This issue is fixed in iOS 27 and iPadOS 27, macOS Golden Gate 27, visionOS 27, watchOS 27. An app may be able to fingerprint the user.

A validation issue existed in the entitlement verification. This issue was addressed with improved validation of the process entitlement. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. A malicious app may be able to break out of its sandbox.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Golden Gate 27. A local attacker may be able to cause unexpected system termination or corrupt kernel memory.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

Accelerate Framework. An out-of-bounds write issue was addressed with improved bounds checking.

A path traversal issue was addressed with improved path validation. This issue is fixed in macOS Golden Gate 27. An app may be able to break out of its sandbox.

Chromium CVE-2026-87609: Use after free in Sharing

Chromium CVE-2026-87470: Improper quantity validation in Tint