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Fencer Intel
high 7.5

GHSA-8fh9-c4jq-94h4 json

idunno.Bluesky, idunno.AtProto and idunno.AtProto.OAuthCallback Denial of Service Vulnerability

published 8mo ago modified 8mo ago

cvss
7.5
version 3.1, GitHub
cisa kev
Not listed
not in CISA's catalog
epss
—
no score, EPSS covers CVEs only
public exploits
0
none known

Summary

# idunno.Bluesky, idunno.AtProto and idunno.AtProto.OAuthCallback Denial of Service Vulnerability

## Impact

The `Microsoft.Bcl.Memory` package, a transitive dependency of `idunno.AtProto` and `idunno.AtProto.OAuthCallback` had a Denial of Service security vulnerability, [CVE-2026-26127](https://github.com/dotnet/announcements/issues/384)

## Patches

v1.7.0 updates the dependencies on `Duende.IdentityModel.OidcClient` and `Duende.IdentityModel.OidcClient.Extensions` which, in turn, updates their dependency on `Microsoft.Bcl.Memory` to 10.0.4, resolving the vulnerability.

## Workarounds

No workarounds exist for this vulnerability.

## How to fix the issue

To update your dependencies on `idunno.Bluesky`, `idunno.AtProto` and `idunno.AtProto.OAuthCallback`,

### Using the .NET CLI (Command Line Interface):

* Open a terminal or command prompt in your project's directory. * To update a specific package to its latest version, use the following add package command:

* If you are using `idunno.Bluesky` `dotnet package update idunno.Bluesky`

* If you are using `idunno.AtProto` as a direct dependency `dotnet package update idunno.AtProto`

* If you are using `idunno.AtProto.OAuthCallback` as a direct dependency `dotnet package update idunno.AtProto.OAuthCallback`

### Using the NuGet Package Manager Console in Visual Studio:

* Open your project in Visual Studio. * Navigate to "Tools > NuGet Package Manager > Package Manager Console". * To update a specific package to its latest version, use the following Update-Package command:

* If you are using `idunno.Bluesky` `Update-Package -Id idunno.Bluesky`

* If you are using `idunno.AtProto` as a direct dependency `Update-Package -Id idunno.AtProto`

* If you are using `idunno.AtProto.OAuthCallback` as a direct dependency `Update-Package -Id idunno.AtProto.OAuthCallback`

### NuGet Package Manager UI in Visual Studio:

* Open your project in Visual Studio. * Right-click on your project in Solution Explorer and select "Manage NuGet Packages..." or navigate to "Project > Manage NuGet Packages". * In the NuGet Package Manager window, select the "Updates" tab. This tab lists packages with available updates from your configured package sources. * Select the package(s) you wish to update. You can choose a specific version from the dropdown or update to the latest available version. * Click the "Update" button.

## References

* [Microsoft Security Advisory CVE-2026-26127 – .NET Denial of Service Vulnerability](https://github.com/dotnet/announcements/issues/384) * [CVE-2026-26127](https://www.cve.org/CVERecord?id=CVE-2026-26127)

Patch / fix

  • nuget idunno.AtProto 1.7.0
  • nuget idunno.AtProto.OAuthCallback 1.7.0
  • nuget idunno.Bluesky 1.7.0

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CVSS scores

assigned by version score vector
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
nuget idunno.AtProto
<1.7.0
1.7.0
nuget idunno.AtProto.OAuthCallback
<1.7.0
1.7.0
nuget idunno.Bluesky
<1.7.0
1.7.0

Classification

Weakness
  • CWE-129 Improper Validation of Array Index

References

Sources

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