fix(ddd): restrict dynamic sorting selectors to property/field access

hooks System.Linq.Dynamic.Core's QueryOptimizer so OrderBy / ThenBy
selectors derived from ISortedResultRequest.Sorting are constrained to
plain property or field access; anything else throws AbpValidationException

framework/src/Volo.Abp.Ddd.Application/Volo/Abp/Application/AbpDddApplicationModule.cs

@@ -30,6 +30,11 @@ namespace Volo.Abp.Application;
     )]
 public class AbpDddApplicationModule : AbpModule
 {
+    public override void PreConfigureServices(ServiceConfigurationContext context)
+    {
+        AbpDynamicSortingGuard.Install();
+    }
+
     public override void ConfigureServices(ServiceConfigurationContext context)
     {
         Configure<AbpApiDescriptionModelOptions>(options =>

framework/src/Volo.Abp.Ddd.Application/Volo/Abp/Application/Services/AbpDynamicSortingGuard.cs

@@ -0,0 +1,95 @@
+using System;
+using System.Linq;
+using System.Linq.Dynamic.Core;
+using System.Linq.Expressions;
+using System.Runtime.CompilerServices;
+using Volo.Abp.Validation;
+
+[assembly: InternalsVisibleTo("Volo.Abp.Ddd.Application.Tests")]
+
+namespace Volo.Abp.Application.Services;
+
+/// <summary>
+/// Framework infrastructure. Hooks <see cref="ExtensibilityPoint.QueryOptimizer"/> so
+/// every OrderBy / ThenBy expression built from a user-supplied sorting string is
+/// constrained to plain property or field access. Methods, comparisons, ternaries
+/// and constants in the sort key are rejected with <see cref="AbpValidationException"/>.
+/// </summary>
+internal static class AbpDynamicSortingGuard
+{
+    private static readonly object InstallLock = new();
+    private static Func<Expression, Expression>? _activeOptimizer;
+
+    public static void Install()
+    {
+        lock (InstallLock)
+        {
+            var current = ExtensibilityPoint.QueryOptimizer;
+            if (_activeOptimizer != null && ReferenceEquals(current, _activeOptimizer))
+            {
+                return;
+            }
+
+            var previous = current;
+            _activeOptimizer = expression =>
+            {
+                new OrderByMethodVisitor().Visit(expression);
+                return previous != null ? previous(expression) : expression;
+            };
+            ExtensibilityPoint.QueryOptimizer = _activeOptimizer;
+        }
+    }
+
+    internal static void Reset()
+    {
+        lock (InstallLock)
+        {
+            if (ReferenceEquals(ExtensibilityPoint.QueryOptimizer, _activeOptimizer))
+            {
+                ExtensibilityPoint.QueryOptimizer = null;
+            }
+            _activeOptimizer = null;
+        }
+    }
+
+    private sealed class OrderByMethodVisitor : ExpressionVisitor
+    {
+        protected override Expression VisitMethodCall(MethodCallExpression node)
+        {
+            if (node.Method.DeclaringType == typeof(Queryable) &&
+                IsOrderByMethod(node.Method.Name) &&
+                node.Arguments.Count >= 2 &&
+                node.Arguments[1] is UnaryExpression { Operand: LambdaExpression lambda })
+            {
+                new PropertyOnlySelectorVisitor().Visit(lambda.Body);
+            }
+
+            return base.VisitMethodCall(node);
+        }
+
+        private static bool IsOrderByMethod(string name)
+        {
+            return name == nameof(Queryable.OrderBy)
+                || name == nameof(Queryable.OrderByDescending)
+                || name == nameof(Queryable.ThenBy)
+                || name == nameof(Queryable.ThenByDescending);
+        }
+    }
+
+    private sealed class PropertyOnlySelectorVisitor : ExpressionVisitor
+    {
+        private const string Message = "Sorting expression is not supported.";
+
+        protected override Expression VisitMethodCall(MethodCallExpression node)
+            => throw new AbpValidationException(Message);
+
+        protected override Expression VisitBinary(BinaryExpression node)
+            => throw new AbpValidationException(Message);
+
+        protected override Expression VisitConditional(ConditionalExpression node)
+            => throw new AbpValidationException(Message);
+
+        protected override Expression VisitConstant(ConstantExpression node)
+            => throw new AbpValidationException(Message);
+    }
+}

framework/test/Volo.Abp.Ddd.Application.Tests/Volo.Abp.Ddd.Application.Tests.abppkg

@@ -0,0 +1,3 @@
+{
+  "role": "lib.test"
+}

framework/test/Volo.Abp.Ddd.Application.Tests/Volo.Abp.Ddd.Application.Tests.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <Import Project="..\..\..\common.test.props" />
+
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <RootNamespace />
+    </PropertyGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\..\src\Volo.Abp.Autofac\Volo.Abp.Autofac.csproj" />
+        <ProjectReference Include="..\..\src\Volo.Abp.Ddd.Application\Volo.Abp.Ddd.Application.csproj" />
+        <ProjectReference Include="..\..\src\Volo.Abp.ExceptionHandling\Volo.Abp.ExceptionHandling.csproj" />
+        <ProjectReference Include="..\AbpTestBase\AbpTestBase.csproj" />
+        <PackageReference Include="Microsoft.NET.Test.Sdk" />
+    </ItemGroup>
+
+</Project>

framework/test/Volo.Abp.Ddd.Application.Tests/Volo/Abp/Application/AbpDddApplicationTestBase.cs

@@ -0,0 +1,12 @@
+using Volo.Abp.Modularity;
+using Volo.Abp.Testing;
+
+namespace Volo.Abp.Application;
+
+public abstract class AbpDddApplicationTestBase : AbpIntegratedTest<AbpDddApplicationTestModule>
+{
+    protected override void SetAbpApplicationCreationOptions(AbpApplicationCreationOptions options)
+    {
+        options.UseAutofac();
+    }
+}

framework/test/Volo.Abp.Ddd.Application.Tests/Volo/Abp/Application/AbpDddApplicationTestModule.cs

@@ -0,0 +1,12 @@
+using Volo.Abp.Autofac;
+using Volo.Abp.ExceptionHandling;
+using Volo.Abp.Modularity;
+
+namespace Volo.Abp.Application;
+
+[DependsOn(typeof(AbpAutofacModule))]
+[DependsOn(typeof(AbpDddApplicationModule))]
+[DependsOn(typeof(AbpExceptionHandlingModule))]
+public class AbpDddApplicationTestModule : AbpModule
+{
+}

framework/test/Volo.Abp.Ddd.Application.Tests/Volo/Abp/Application/Services/AbpDynamicSortingGuard_Tests.cs

@@ -0,0 +1,131 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Dynamic.Core;
+using Shouldly;
+using Volo.Abp.Validation;
+using Xunit;
+
+namespace Volo.Abp.Application.Services;
+
+public class AbpDynamicSortingGuard_Tests : AbpDddApplicationTestBase
+{
+    private readonly IQueryable<FakeUser> _users;
+
+    public AbpDynamicSortingGuard_Tests()
+    {
+        _users = new List<FakeUser>
+        {
+            new() { Name = "alice", Age = 30, PasswordHash = "AQAAhash_alice", Tenant = new FakeTenant { Name = "acme" } },
+            new() { Name = "bob",   Age = 25, PasswordHash = "BQAAhash_bob",   Tenant = new FakeTenant { Name = "beta" } },
+            new() { Name = "carl",  Age = 40, PasswordHash = "CQAAhash_carl",  Tenant = new FakeTenant { Name = "corp" } },
+        }.AsQueryable();
+    }
+
+    [Theory]
+    [InlineData("Name")]
+    [InlineData("Name desc")]
+    [InlineData("Name asc, PasswordHash desc")]
+    [InlineData("Age desc")] // value type → EF/Dynamic.Core wraps selector in Convert(MemberAccess, object)
+    [InlineData("Tenant.Name")] // chained MemberAccess
+    [InlineData("Tenant.Name desc, Age asc")] // mixed chained + value-type, multi-column
+    [InlineData("Name.Length desc")] // Length is a property getter, not a method call
+    public void Should_Accept_Plain_Property_Sorting(string sorting)
+    {
+        Should.NotThrow(() => _users.OrderBy(sorting).ToList());
+    }
+
+    [Theory]
+    [InlineData("PasswordHash.Substring(0,1) desc")]
+    [InlineData("PasswordHash.StartsWith(\"A\") desc")]
+    [InlineData("PasswordHash.Contains(\"hash\") desc")]
+    [InlineData("Name asc, PasswordHash.Substring(0,1) desc")] // multi-column with attack in 2nd
+    public void Should_Reject_Method_Call_On_Property(string sorting)
+    {
+        Should.Throw<AbpValidationException>(() => _users.OrderBy(sorting).ToList())
+            .Message.ShouldBe("Sorting expression is not supported.");
+    }
+
+    [Theory]
+    [InlineData("(PasswordHash == \"AQAA\") desc")]
+    [InlineData("(PasswordHash > \"M\") desc")]
+    [InlineData("(PasswordHash != \"AQAA\") asc")]
+    public void Should_Reject_Binary_Expressions(string sorting)
+    {
+        Should.Throw<AbpValidationException>(() => _users.OrderBy(sorting).ToList())
+            .Message.ShouldBe("Sorting expression is not supported.");
+    }
+
+    [Fact]
+    public void Should_Not_Affect_Where_Expressions()
+    {
+        // The guard only inspects Queryable.OrderBy/ThenBy nodes. Where with the same
+        // sub-expression is left alone (Where is a separate vulnerability class).
+        Should.NotThrow(() => _users.Where("PasswordHash.StartsWith(\"A\")").ToList());
+    }
+
+    [Fact]
+    public void Install_Chains_Existing_QueryOptimizer()
+    {
+        // Reset guard state so Install() actually re-installs and exercises the
+        // `previous != null ? previous(expression) : expression` branch.
+        AbpDynamicSortingGuard.Reset();
+        try
+        {
+            var preExistingFired = false;
+            ExtensibilityPoint.QueryOptimizer = e =>
+            {
+                preExistingFired = true;
+                return e;
+            };
+
+            AbpDynamicSortingGuard.Install();
+
+            _users.OrderBy("Name").ToList();
+            preExistingFired.ShouldBeTrue();
+        }
+        finally
+        {
+            // Leave the AppDomain with a single-layer guard. Reset() clears whatever
+            // we wrapped in this test; Install() then puts a fresh guard on top of
+            // an empty QueryOptimizer — never double-wraps an existing guard.
+            AbpDynamicSortingGuard.Reset();
+            AbpDynamicSortingGuard.Install();
+        }
+    }
+
+    [Fact]
+    public void Install_Reinstalls_When_QueryOptimizer_Was_Replaced()
+    {
+        // Simulate someone (e.g. a test teardown, another module) overwriting our
+        // optimizer. The next Install() must detect the mismatch and wrap again.
+        try
+        {
+            ExtensibilityPoint.QueryOptimizer = e => e; // not our wrapper
+
+            AbpDynamicSortingGuard.Install();
+
+            // Guard must be active again — attack payload still gets rejected.
+            Should.Throw<AbpValidationException>(() =>
+                _users.OrderBy("PasswordHash.Substring(0,1) desc").ToList());
+        }
+        finally
+        {
+            AbpDynamicSortingGuard.Reset();
+            AbpDynamicSortingGuard.Install();
+        }
+    }
+
+    private class FakeUser
+    {
+        public string Name { get; set; } = "";
+        public int Age { get; set; }
+        public string PasswordHash { get; set; } = "";
+        public FakeTenant Tenant { get; set; } = new();
+    }
+
+    private class FakeTenant
+    {
+        public string Name { get; set; } = "";
+    }
+}