diff --git a/.config/dotnet-tools.json b/.config/dotnet-tools.json
index a3850de029..e29d6594ea 100644
--- a/.config/dotnet-tools.json
+++ b/.config/dotnet-tools.json
@@ -7,7 +7,7 @@
       "commands": ["swagger"]
     },
     "dotnet-ef": {
-      "version": "7.0.15",
+      "version": "8.0.0",
       "commands": ["dotnet-ef"]
     }
   }
diff --git a/Directory.Build.props b/Directory.Build.props
index 376ab13177..8cfc297865 100644
--- a/Directory.Build.props
+++ b/Directory.Build.props
@@ -1,8 +1,10 @@
 <Project>
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
+
     <Version>2024.2.0</Version>
+
     <RootNamespace>Bit.$(MSBuildProjectName)</RootNamespace>
     <ImplicitUsings>enable</ImplicitUsings>
     <IncludeSourceRevisionInInformationalVersion>false</IncludeSourceRevisionInInformationalVersion>
@@ -17,31 +19,31 @@
     <!--
       NuGet: https://www.nuget.org/packages/Microsoft.NET.Test.Sdk
     -->
-    <MicrosoftNetTestSdkVersion>17.1.0</MicrosoftNetTestSdkVersion>
+    <MicrosoftNetTestSdkVersion>17.8.0</MicrosoftNetTestSdkVersion>
     <!--
       NuGet: https://www.nuget.org/packages/xunit
     -->
-    <XUnitVersion>2.4.1</XUnitVersion>
+    <XUnitVersion>2.6.6</XUnitVersion>
     <!--
-      NuGet: https://www.nuget.org/packages/xunit
+      NuGet: https://www.nuget.org/packages/xunit.runner.visualstudio
     -->
-    <XUnitRunnerVisualStudioVersion>2.4.3</XUnitRunnerVisualStudioVersion>
+    <XUnitRunnerVisualStudioVersion>2.5.6</XUnitRunnerVisualStudioVersion>
     <!--
-      NuGet: https://www.nuget.org/packages/coverlet.collector/
+      NuGet: https://www.nuget.org/packages/coverlet.collector
     -->
-    <CoverletCollectorVersion>3.1.2</CoverletCollectorVersion>
+    <CoverletCollectorVersion>6.0.0</CoverletCollectorVersion>
     <!--
-      NuGet: https://www.nuget.org/packages/NSubstitute/
+      NuGet: https://www.nuget.org/packages/NSubstitute
     -->
-    <NSubstituteVersion>4.3.0</NSubstituteVersion>
+    <NSubstituteVersion>5.1.0</NSubstituteVersion>
     <!--
-      NuGet: https://www.nuget.org/packages/AutoFixture.Xunit2/
+      NuGet: https://www.nuget.org/packages/AutoFixture.Xunit2
     -->
-    <AutoFixtureXUnit2Version>4.17.0</AutoFixtureXUnit2Version>
+    <AutoFixtureXUnit2Version>4.18.1</AutoFixtureXUnit2Version>
     <!--
-      NuGet: https://www.nuget.org/packages/AutoFixture.AutoNSubstitute/
+      NuGet: https://www.nuget.org/packages/AutoFixture.AutoNSubstitute
     -->
-    <AutoFixtureAutoNSubstituteVersion>4.17.0</AutoFixtureAutoNSubstituteVersion>
+    <AutoFixtureAutoNSubstituteVersion>4.18.1</AutoFixtureAutoNSubstituteVersion>
   </PropertyGroup>
 
   <!--
@@ -62,4 +64,4 @@
     </ItemGroup>
   </Target>
 
-</Project>
\ No newline at end of file
+</Project>
diff --git a/bitwarden_license/src/Scim/Dockerfile b/bitwarden_license/src/Scim/Dockerfile
index f63cb82ce3..ae9e693c2a 100644
--- a/bitwarden_license/src/Scim/Dockerfile
+++ b/bitwarden_license/src/Scim/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/bitwarden_license/src/Sso/Dockerfile b/bitwarden_license/src/Sso/Dockerfile
index f63cb82ce3..ae9e693c2a 100644
--- a/bitwarden_license/src/Sso/Dockerfile
+++ b/bitwarden_license/src/Sso/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/bitwarden_license/src/Sso/Utilities/Saml2BitHandler.cs b/bitwarden_license/src/Sso/Utilities/Saml2BitHandler.cs
index 6e5a37fb96..83705369fb 100644
--- a/bitwarden_license/src/Sso/Utilities/Saml2BitHandler.cs
+++ b/bitwarden_license/src/Sso/Utilities/Saml2BitHandler.cs
@@ -167,7 +167,7 @@ static class CommandResultExtensions
 
         foreach (var h in commandResult.Headers)
         {
-            httpContext.Response.Headers.Add(h.Key, h.Value);
+            httpContext.Response.Headers.Append(h.Key, h.Value);
         }
 
         if (!string.IsNullOrEmpty(commandResult.ClearCookieName))
diff --git a/bitwarden_license/test/Scim.IntegrationTest/Factories/ScimApplicationFactory.cs b/bitwarden_license/test/Scim.IntegrationTest/Factories/ScimApplicationFactory.cs
index 6ebd59283d..bf64f5cee8 100644
--- a/bitwarden_license/test/Scim.IntegrationTest/Factories/ScimApplicationFactory.cs
+++ b/bitwarden_license/test/Scim.IntegrationTest/Factories/ScimApplicationFactory.cs
@@ -90,12 +90,12 @@ public class ScimApplicationFactory : WebApplicationFactoryBase<Startup>
 
     public async Task<HttpContext> GroupsPostAsync(Guid organizationId, ScimGroupRequestModel model)
     {
-        return await Server.PostAsync($"/v2/{organizationId}/groups", GetStringContent(model), httpContext => httpContext.Request.Headers.Add(HeaderNames.UserAgent, "Okta"));
+        return await Server.PostAsync($"/v2/{organizationId}/groups", GetStringContent(model), httpContext => httpContext.Request.Headers.Append(HeaderNames.UserAgent, "Okta"));
     }
 
     public async Task<HttpContext> GroupsPutAsync(Guid organizationId, Guid id, ScimGroupRequestModel model)
     {
-        return await Server.PutAsync($"/v2/{organizationId}/groups/{id}", GetStringContent(model), httpContext => httpContext.Request.Headers.Add(HeaderNames.UserAgent, "Okta"));
+        return await Server.PutAsync($"/v2/{organizationId}/groups/{id}", GetStringContent(model), httpContext => httpContext.Request.Headers.Append(HeaderNames.UserAgent, "Okta"));
     }
 
     public async Task<HttpContext> GroupsPatchAsync(Guid organizationId, Guid id, ScimPatchModel model)
diff --git a/global.json b/global.json
index 10b65be864..391ba3c2a3 100644
--- a/global.json
+++ b/global.json
@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "6.0.100",
+    "version": "8.0.100",
     "rollForward": "latestFeature"
   }
 }
diff --git a/perf/MicroBenchmarks/MicroBenchmarks.csproj b/perf/MicroBenchmarks/MicroBenchmarks.csproj
index d3ee14a684..ce2d2fdbcb 100644
--- a/perf/MicroBenchmarks/MicroBenchmarks.csproj
+++ b/perf/MicroBenchmarks/MicroBenchmarks.csproj
@@ -2,7 +2,6 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
   </PropertyGroup>
diff --git a/src/Admin/Dockerfile b/src/Admin/Dockerfile
index 1c2264bf20..54ecbac0d6 100644
--- a/src/Admin/Dockerfile
+++ b/src/Admin/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/src/Admin/HostedServices/AzureQueueMailHostedService.cs b/src/Admin/HostedServices/AzureQueueMailHostedService.cs
index b2031a405b..cff724e4f3 100644
--- a/src/Admin/HostedServices/AzureQueueMailHostedService.cs
+++ b/src/Admin/HostedServices/AzureQueueMailHostedService.cs
@@ -67,14 +67,14 @@ public class AzureQueueMailHostedService : IHostedService
 
                     if (root.ValueKind == JsonValueKind.Array)
                     {
-                        foreach (var mailQueueMessage in root.ToObject<List<MailQueueMessage>>())
+                        foreach (var mailQueueMessage in root.Deserialize<List<MailQueueMessage>>())
                         {
                             await _mailService.SendEnqueuedMailMessageAsync(mailQueueMessage);
                         }
                     }
                     else if (root.ValueKind == JsonValueKind.Object)
                     {
-                        var mailQueueMessage = root.ToObject<MailQueueMessage>();
+                        var mailQueueMessage = root.Deserialize<MailQueueMessage>();
                         await _mailService.SendEnqueuedMailMessageAsync(mailQueueMessage);
                     }
                 }
diff --git a/src/Api/AdminConsole/Models/Request/Organizations/OrganizationConnectionRequestModel.cs b/src/Api/AdminConsole/Models/Request/Organizations/OrganizationConnectionRequestModel.cs
index 1883d34afb..d7508b78ef 100644
--- a/src/Api/AdminConsole/Models/Request/Organizations/OrganizationConnectionRequestModel.cs
+++ b/src/Api/AdminConsole/Models/Request/Organizations/OrganizationConnectionRequestModel.cs
@@ -31,7 +31,7 @@ public class OrganizationConnectionRequestModel<T> : OrganizationConnectionReque
 
         try
         {
-            ParsedConfig = model.Config.ToObject<T>(JsonHelpers.IgnoreCase);
+            ParsedConfig = model.Config.Deserialize<T>(JsonHelpers.IgnoreCase);
         }
         catch (JsonException)
         {
diff --git a/src/Api/Dockerfile b/src/Api/Dockerfile
index f63cb82ce3..ae9e693c2a 100644
--- a/src/Api/Dockerfile
+++ b/src/Api/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/src/Billing/Dockerfile b/src/Billing/Dockerfile
index cd00c068f7..9abbe16477 100644
--- a/src/Billing/Dockerfile
+++ b/src/Billing/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/src/Core/AdminConsole/OrganizationFeatures/OrganizationDomains/CreateOrganizationDomainCommand.cs b/src/Core/AdminConsole/OrganizationFeatures/OrganizationDomains/CreateOrganizationDomainCommand.cs
index ea02a65a38..35fa54faa7 100644
--- a/src/Core/AdminConsole/OrganizationFeatures/OrganizationDomains/CreateOrganizationDomainCommand.cs
+++ b/src/Core/AdminConsole/OrganizationFeatures/OrganizationDomains/CreateOrganizationDomainCommand.cs
@@ -59,7 +59,7 @@ public class CreateOrganizationDomainCommand : ICreateOrganizationDomainCommand
         }
         catch (Exception e)
         {
-            _logger.LogError("Error verifying Organization domain.", e);
+            _logger.LogError(e, "Error verifying Organization domain.");
         }
 
         organizationDomain.SetNextRunDate(_globalSettings.DomainVerification.VerificationInterval);
diff --git a/src/Core/OrganizationFeatures/OrganizationSponsorships/FamiliesForEnterprise/Cloud/ValidateSponsorshipCommand.cs b/src/Core/OrganizationFeatures/OrganizationSponsorships/FamiliesForEnterprise/Cloud/ValidateSponsorshipCommand.cs
index 83a0249e80..97b6b18e44 100644
--- a/src/Core/OrganizationFeatures/OrganizationSponsorships/FamiliesForEnterprise/Cloud/ValidateSponsorshipCommand.cs
+++ b/src/Core/OrganizationFeatures/OrganizationSponsorships/FamiliesForEnterprise/Cloud/ValidateSponsorshipCommand.cs
@@ -88,7 +88,7 @@ public class ValidateSponsorshipCommand : CancelSponsorshipCommand, IValidateSpo
             }
             catch (Exception e)
             {
-                _logger.LogError("Error sending Family sponsorship removed email.", e);
+                _logger.LogError(e, "Error sending Family sponsorship removed email.");
             }
         }
         await base.DeleteSponsorshipAsync(sponsorship);
diff --git a/src/Core/Utilities/JsonHelpers.cs b/src/Core/Utilities/JsonHelpers.cs
index ad7aefd257..77ab866676 100644
--- a/src/Core/Utilities/JsonHelpers.cs
+++ b/src/Core/Utilities/JsonHelpers.cs
@@ -45,18 +45,6 @@ public static class JsonHelpers
         };
     }
 
-    [Obsolete("This is built into .NET 6, it SHOULD be removed when we upgrade")]
-    public static T ToObject<T>(this JsonElement element, JsonSerializerOptions options = null)
-    {
-        return JsonSerializer.Deserialize<T>(element.GetRawText(), options ?? Default);
-    }
-
-    [Obsolete("This is built into .NET 6, it SHOULD be removed when we upgrade")]
-    public static T ToObject<T>(this JsonDocument document, JsonSerializerOptions options = null)
-    {
-        return JsonSerializer.Deserialize<T>(document.RootElement.GetRawText(), options ?? default);
-    }
-
     public static T DeserializeOrNew<T>(string json, JsonSerializerOptions options = null)
         where T : new()
     {
diff --git a/src/Core/Utilities/SecurityHeadersMiddleware.cs b/src/Core/Utilities/SecurityHeadersMiddleware.cs
index 19616e8a74..1ed8bd4536 100644
--- a/src/Core/Utilities/SecurityHeadersMiddleware.cs
+++ b/src/Core/Utilities/SecurityHeadersMiddleware.cs
@@ -15,13 +15,13 @@ public sealed class SecurityHeadersMiddleware
     public Task Invoke(HttpContext context)
     {
         // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options
-        context.Response.Headers.Add("x-frame-options", new StringValues("SAMEORIGIN"));
+        context.Response.Headers.Append("x-frame-options", new StringValues("SAMEORIGIN"));
 
         // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-XSS-Protection
-        context.Response.Headers.Add("x-xss-protection", new StringValues("1; mode=block"));
+        context.Response.Headers.Append("x-xss-protection", new StringValues("1; mode=block"));
 
         // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Content-Type-Options
-        context.Response.Headers.Add("x-content-type-options", new StringValues("nosniff"));
+        context.Response.Headers.Append("x-content-type-options", new StringValues("nosniff"));
 
         return _next(context);
     }
diff --git a/src/Core/Utilities/SpanExtensions.cs b/src/Core/Utilities/SpanExtensions.cs
index 1bd18d2981..16e767079c 100644
--- a/src/Core/Utilities/SpanExtensions.cs
+++ b/src/Core/Utilities/SpanExtensions.cs
@@ -18,21 +18,4 @@ public static class SpanExtensions
         rest = input[++splitIndex..];
         return true;
     }
-
-    // Replace with the implementation from .NET 8 when we upgrade
-    // Ref: https://github.com/dotnet/runtime/issues/59466
-    public static int Count<T>(this ReadOnlySpan<T> span, T value)
-        where T : IEquatable<T>
-    {
-        var count = 0;
-        int pos;
-
-        while ((pos = span.IndexOf(value)) >= 0)
-        {
-            span = span[++pos..];
-            count++;
-        }
-
-        return count;
-    }
 }
diff --git a/src/Events/Dockerfile b/src/Events/Dockerfile
index f63cb82ce3..ae9e693c2a 100644
--- a/src/Events/Dockerfile
+++ b/src/Events/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/src/EventsProcessor/AzureQueueHostedService.cs b/src/EventsProcessor/AzureQueueHostedService.cs
index 837e4ad148..03c0034539 100644
--- a/src/EventsProcessor/AzureQueueHostedService.cs
+++ b/src/EventsProcessor/AzureQueueHostedService.cs
@@ -104,13 +104,13 @@ public class AzureQueueHostedService : IHostedService, IDisposable
             var root = jsonDocument.RootElement;
             if (root.ValueKind == JsonValueKind.Array)
             {
-                var indexedEntities = root.ToObject<List<EventMessage>>()
+                var indexedEntities = root.Deserialize<List<EventMessage>>()
                     .SelectMany(e => EventTableEntity.IndexEvent(e));
                 events.AddRange(indexedEntities);
             }
             else if (root.ValueKind == JsonValueKind.Object)
             {
-                var eventMessage = root.ToObject<EventMessage>();
+                var eventMessage = root.Deserialize<EventMessage>();
                 events.AddRange(EventTableEntity.IndexEvent(eventMessage));
             }
 
diff --git a/src/EventsProcessor/Dockerfile b/src/EventsProcessor/Dockerfile
index 3d505d28ef..4344452f65 100644
--- a/src/EventsProcessor/Dockerfile
+++ b/src/EventsProcessor/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/src/Icons/Dockerfile b/src/Icons/Dockerfile
index 42514c613e..edc1e0905b 100644
--- a/src/Icons/Dockerfile
+++ b/src/Icons/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/src/Identity/Dockerfile b/src/Identity/Dockerfile
index 6d1adfd484..d93414a456 100644
--- a/src/Identity/Dockerfile
+++ b/src/Identity/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/src/Notifications/Dockerfile b/src/Notifications/Dockerfile
index f63cb82ce3..ae9e693c2a 100644
--- a/src/Notifications/Dockerfile
+++ b/src/Notifications/Dockerfile
@@ -1,11 +1,11 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        gosu \
-        curl \
+    gosu \
+    curl \
     && rm -rf /var/lib/apt/lists/*
 
 ENV ASPNETCORE_URLS http://+:5000
diff --git a/test/Core.Test/AdminConsole/Services/OrganizationServiceTests.cs b/test/Core.Test/AdminConsole/Services/OrganizationServiceTests.cs
index 5f6aa08663..4c83e08287 100644
--- a/test/Core.Test/AdminConsole/Services/OrganizationServiceTests.cs
+++ b/test/Core.Test/AdminConsole/Services/OrganizationServiceTests.cs
@@ -96,7 +96,7 @@ public class OrganizationServiceTests
         await sutProvider.GetDependency<IOrganizationUserRepository>().DidNotReceiveWithAnyArgs()
             .UpsertAsync(default);
         await sutProvider.GetDependency<IOrganizationUserRepository>().Received(1)
-            .UpsertManyAsync(Arg.Is<IEnumerable<OrganizationUser>>(users => users.Count() == 0));
+            .UpsertManyAsync(Arg.Is<IEnumerable<OrganizationUser>>(users => !users.Any()));
         await sutProvider.GetDependency<IOrganizationUserRepository>().DidNotReceiveWithAnyArgs()
             .CreateAsync(default);
 
diff --git a/test/Core.Test/Services/DeviceServiceTests.cs b/test/Core.Test/Services/DeviceServiceTests.cs
index bdd3fbdad0..cb2aebc992 100644
--- a/test/Core.Test/Services/DeviceServiceTests.cs
+++ b/test/Core.Test/Services/DeviceServiceTests.cs
@@ -41,7 +41,7 @@ public class DeviceServiceTests
     }
 
     /// <summary>
-    /// Story: A user choosed to keep trust in one of their current trusted devices, but not in another one of their
+    /// Story: A user chose to keep trust in one of their current trusted devices, but not in another one of their
     /// devices. We will rotate the trust of the currently signed in device as well as the device they chose but will
     /// remove the trust of the device they didn't give new keys for.
     /// </summary>
@@ -117,8 +117,7 @@ public class DeviceServiceTests
             .Received(3)
             .UpsertAsync(Arg.Any<Device>());
 
-        // TODO: .NET 8: Use nameof for parameter name.
-        static void SetupOldTrust(Device device, [CallerArgumentExpression("device")] string expression = null)
+        static void SetupOldTrust(Device device, [CallerArgumentExpression(nameof(device))] string expression = null)
         {
             device.EncryptedPublicKey = $"old_public_{expression}";
             device.EncryptedPrivateKey = $"old_private_{expression}";
diff --git a/test/Core.Test/Utilities/SpanExtensionsTests.cs b/test/Core.Test/Utilities/SpanExtensionsTests.cs
index ca0ce7fba6..5e8fa92b63 100644
--- a/test/Core.Test/Utilities/SpanExtensionsTests.cs
+++ b/test/Core.Test/Utilities/SpanExtensionsTests.cs
@@ -31,22 +31,4 @@ public class SpanExtensionsTests
         Assert.True(splitChunk.IsEmpty);
         Assert.Equal(fullString, rest.ToString());
     }
-
-    [Theory]
-    [InlineData("11111", '1', 5)]
-    [InlineData("Text", 'z', 0)]
-    [InlineData("1", '1', 1)]
-    public void Count_ReturnsCount(string text, char countChar, int expectedInstances)
-    {
-        Assert.Equal(expectedInstances, text.AsSpan().Count(countChar));
-    }
-
-    [Theory]
-    [InlineData(new[] { 5, 4 }, 5, 1)]
-    [InlineData(new[] { 1 }, 5, 0)]
-    [InlineData(new[] { 5, 5, 5 }, 5, 3)]
-    public void CountIntegers_ReturnsCount(int[] array, int countNumber, int expectedInstances)
-    {
-        Assert.Equal(expectedInstances, ((ReadOnlySpan<int>)array.AsSpan()).Count(countNumber));
-    }
 }
diff --git a/test/Core.Test/Vault/Services/CipherServiceTests.cs b/test/Core.Test/Vault/Services/CipherServiceTests.cs
index a4eb05ac4f..b23c4ed9d2 100644
--- a/test/Core.Test/Vault/Services/CipherServiceTests.cs
+++ b/test/Core.Test/Vault/Services/CipherServiceTests.cs
@@ -15,7 +15,6 @@ using Bit.Core.Vault.Repositories;
 using Bit.Core.Vault.Services;
 using Bit.Test.Common.AutoFixture;
 using Bit.Test.Common.AutoFixture.Attributes;
-using Castle.Core.Internal;
 using NSubstitute;
 using Xunit;
 
@@ -75,7 +74,7 @@ public class CipherServiceTests
                         !cols.Any(c => c.Id == collections[0].Id) && // Check that the collection that already existed in the organization was not added
                         cols.All(c => collections.Any(x => c.Name == x.Name))),
             Arg.Is<IEnumerable<CollectionCipher>>(c => c.Count() == ciphers.Count),
-            Arg.Is<IEnumerable<CollectionUser>>(i => i.IsNullOrEmpty()));
+            Arg.Is<IEnumerable<CollectionUser>>(i => !i.Any()));
         await sutProvider.GetDependency<IPushNotificationService>().Received(1).PushSyncVaultAsync(importingUserId);
         await sutProvider.GetDependency<IReferenceEventService>().Received(1).RaiseEventAsync(
             Arg.Is<ReferenceEvent>(e => e.Type == ReferenceEventType.VaultImported));
@@ -683,7 +682,7 @@ public class CipherServiceTests
 
         await sutProvider.Sut.ShareManyAsync(cipherInfos, organization.Id, collectionIds, sharingUserId);
         await sutProvider.GetDependency<ICipherRepository>().Received(1).UpdateCiphersAsync(sharingUserId,
-            Arg.Is<IEnumerable<Cipher>>(arg => arg.Except(ciphers).IsNullOrEmpty()));
+            Arg.Is<IEnumerable<Cipher>>(arg => !arg.Except(ciphers).Any()));
     }
 
     [Theory]
@@ -839,7 +838,7 @@ public class CipherServiceTests
 
         await sutProvider.Sut.ShareManyAsync(cipherInfos, organizationId, collectionIds, sharingUserId);
         await sutProvider.GetDependency<ICipherRepository>().Received(1).UpdateCiphersAsync(sharingUserId,
-            Arg.Is<IEnumerable<Cipher>>(arg => arg.Except(ciphers).IsNullOrEmpty()));
+            Arg.Is<IEnumerable<Cipher>>(arg => !arg.Except(ciphers).Any()));
     }
 
     private async Task AssertNoActionsAsync(SutProvider<CipherService> sutProvider)
diff --git a/test/Icons.Test/Models/IconLinkTests.cs b/test/Icons.Test/Models/IconLinkTests.cs
index db4399670c..3801558d8d 100644
--- a/test/Icons.Test/Models/IconLinkTests.cs
+++ b/test/Icons.Test/Models/IconLinkTests.cs
@@ -68,11 +68,11 @@ public class IconLinkTests
     }
 
     [Fact]
-    public void FetchAsync_Unvalidated_ReturnsNull()
+    public async Task FetchAsync_Unvalidated_ReturnsNull()
     {
-        var result = new IconLink(_element, _uri, _baseUrlPath).FetchAsync(_logger, _httpClientFactory, _uriService);
+        var result = await new IconLink(_element, _uri, _baseUrlPath).FetchAsync(_logger, _httpClientFactory, _uriService);
 
-        Assert.Null(result.Result);
+        Assert.Null(result);
     }
 
     private void SetAttributeValue(string attribute, string value)
diff --git a/test/Icons.Test/Services/IconFetchingServiceTests.cs b/test/Icons.Test/Services/IconFetchingServiceTests.cs
index ad73a2cfc9..cc23975ec5 100644
--- a/test/Icons.Test/Services/IconFetchingServiceTests.cs
+++ b/test/Icons.Test/Services/IconFetchingServiceTests.cs
@@ -11,9 +11,8 @@ public class IconFetchingServiceTests : ServiceTestBase<IconFetchingService>
     [InlineData("neverssl.com")] // http site
     [InlineData("neopets.com")] // uses favicon.ico
     [InlineData("hopin.com")] // uses svg+xml format
-    [InlineData("ameritrade.com")] // redirects to tdameritrace.com
+    [InlineData("ameritrade.com")] // redirects to tdameritrade.com
     [InlineData("icloud.com")]
-    [InlineData("bofa.com", Skip = "Broken in pipeline for .NET 6. Tracking link: https://bitwarden.atlassian.net/browse/PS-982")]
     public async Task GetIconAsync_Success(string domain)
     {
         var sut = BuildSut();
diff --git a/test/Identity.IntegrationTest/Endpoints/IdentityServerTests.cs b/test/Identity.IntegrationTest/Endpoints/IdentityServerTests.cs
index 2599559f38..5717bc6d56 100644
--- a/test/Identity.IntegrationTest/Endpoints/IdentityServerTests.cs
+++ b/test/Identity.IntegrationTest/Endpoints/IdentityServerTests.cs
@@ -106,7 +106,7 @@ public class IdentityServerTests : IClassFixture<IdentityApplicationFactory>
             MasterPasswordHash = "master_password_hash",
         });
 
-        var context = await PostLoginAsync(_factory.Server, username, deviceId, context => context.Request.Headers.Add("Auth-Email", "bad_value"));
+        var context = await PostLoginAsync(_factory.Server, username, deviceId, context => context.Request.Headers.Append("Auth-Email", "bad_value"));
 
         Assert.Equal(StatusCodes.Status400BadRequest, context.Response.StatusCode);
 
diff --git a/test/Infrastructure.EFIntegration.Test/AdminConsole/Repositories/OrganizationRepositoryTests.cs b/test/Infrastructure.EFIntegration.Test/AdminConsole/Repositories/OrganizationRepositoryTests.cs
index 3af387475d..e75b3bd6e5 100644
--- a/test/Infrastructure.EFIntegration.Test/AdminConsole/Repositories/OrganizationRepositoryTests.cs
+++ b/test/Infrastructure.EFIntegration.Test/AdminConsole/Repositories/OrganizationRepositoryTests.cs
@@ -183,7 +183,7 @@ public class OrganizationRepositoryTests
 
         Assert.Equal(efOrgRepos.Count, efList.Count);
         Assert.True(efList.All(o => o.Name == org.Name));
-        Assert.Equal(1, sqlResult.Count);
+        Assert.Single(sqlResult);
         Assert.True(sqlResult.All(o => o.Name == org.Name));
     }
 }
diff --git a/test/IntegrationTestCommon/Factories/IdentityApplicationFactory.cs b/test/IntegrationTestCommon/Factories/IdentityApplicationFactory.cs
index d47b3da861..def8f5c14c 100644
--- a/test/IntegrationTestCommon/Factories/IdentityApplicationFactory.cs
+++ b/test/IntegrationTestCommon/Factories/IdentityApplicationFactory.cs
@@ -35,7 +35,7 @@ public class IdentityApplicationFactory : WebApplicationFactoryBase<Startup>
             { "grant_type", "password" },
             { "username", username },
             { "password", password },
-        }), context => context.Request.Headers.Add("Auth-Email", CoreHelpers.Base64UrlEncodeString(username)));
+        }), context => context.Request.Headers.Append("Auth-Email", CoreHelpers.Base64UrlEncodeString(username)));
 
         using var body = await AssertHelper.AssertResponseTypeIs<JsonDocument>(context);
         var root = body.RootElement;
diff --git a/test/IntegrationTestCommon/Factories/WebApplicationFactoryExtensions.cs b/test/IntegrationTestCommon/Factories/WebApplicationFactoryExtensions.cs
index fe9eacc0ab..562156b09e 100644
--- a/test/IntegrationTestCommon/Factories/WebApplicationFactoryExtensions.cs
+++ b/test/IntegrationTestCommon/Factories/WebApplicationFactoryExtensions.cs
@@ -28,7 +28,7 @@ public static class WebApplicationFactoryExtensions
             {
                 foreach (var header in content.Headers)
                 {
-                    httpContext.Request.Headers.Add(header.Key, new StringValues(header.Value.ToArray()));
+                    httpContext.Request.Headers.Append(header.Key, new StringValues(header.Value.ToArray()));
                 }
 
                 httpContext.Request.Body = content.ReadAsStream();
@@ -64,7 +64,7 @@ public static class WebApplicationFactoryExtensions
 
     public static HttpContext SetAuthEmail(this HttpContext context, string username)
     {
-        context.Request.Headers.Add("Auth-Email", CoreHelpers.Base64UrlEncodeString(username));
+        context.Request.Headers.Append("Auth-Email", CoreHelpers.Base64UrlEncodeString(username));
         return context;
     }
 
diff --git a/util/MsSqlMigratorUtility/Dockerfile b/util/MsSqlMigratorUtility/Dockerfile
index 1a33ff12d2..7b53905f49 100644
--- a/util/MsSqlMigratorUtility/Dockerfile
+++ b/util/MsSqlMigratorUtility/Dockerfile
@@ -1,4 +1,4 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
diff --git a/util/Server/Dockerfile b/util/Server/Dockerfile
index e26c9b42dc..6755a85284 100644
--- a/util/Server/Dockerfile
+++ b/util/Server/Dockerfile
@@ -1,4 +1,4 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden"
 
diff --git a/util/Setup/Dockerfile b/util/Setup/Dockerfile
index 6aee1ca315..0d0b0d7648 100644
--- a/util/Setup/Dockerfile
+++ b/util/Setup/Dockerfile
@@ -1,12 +1,12 @@
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 
 LABEL com.bitwarden.product="bitwarden" com.bitwarden.project="setup"
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-        openssl \
-        gosu \
-&& rm -rf /var/lib/apt/lists/*
+    openssl \
+    gosu \
+    && rm -rf /var/lib/apt/lists/*
 
 WORKDIR /app
 COPY obj/build-output/publish .
diff --git a/util/SqliteMigrations/SqliteMigrations.csproj b/util/SqliteMigrations/SqliteMigrations.csproj
index ba322375c4..c3f800bea3 100644
--- a/util/SqliteMigrations/SqliteMigrations.csproj
+++ b/util/SqliteMigrations/SqliteMigrations.csproj
@@ -1,7 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
   </PropertyGroup>