diff --git a/src/OpenIddict.Core/Managers/OpenIddictApplicationManager.cs b/src/OpenIddict.Core/Managers/OpenIddictApplicationManager.cs
index 9e917f21..bcef21ac 100644
--- a/src/OpenIddict.Core/Managers/OpenIddictApplicationManager.cs
+++ b/src/OpenIddict.Core/Managers/OpenIddictApplicationManager.cs
@@ -154,17 +154,31 @@ namespace OpenIddict.Core
         }
 
         /// <summary>
-        /// Retrieves an application using its post_logout_redirect_uri.
+        /// Retrieves all the applications associated with the specified post_logout_redirect_uri.
         /// </summary>
-        /// <param name="url">The post_logout_redirect_uri associated with the application.</param>
+        /// <param name="address">The post_logout_redirect_uri associated with the applications.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> that can be used to abort the operation.</param>
         /// <returns>
         /// A <see cref="Task"/> that can be used to monitor the asynchronous operation, whose result
-        /// returns the client application corresponding to the post_logout_redirect_uri.
+        /// returns the client applications corresponding to the specified post_logout_redirect_uri.
         /// </returns>
-        public virtual Task<TApplication> FindByLogoutRedirectUri(string url, CancellationToken cancellationToken)
+        public virtual Task<TApplication[]> FindByLogoutRedirectUri(string address, CancellationToken cancellationToken)
         {
-            return Store.FindByLogoutRedirectUri(url, cancellationToken);
+            return Store.FindByLogoutRedirectUri(address, cancellationToken);
+        }
+
+        /// <summary>
+        /// Retrieves all the applications associated with the specified redirect_uri.
+        /// </summary>
+        /// <param name="address">The redirect_uri associated with the applications.</param>
+        /// <param name="cancellationToken">The <see cref="CancellationToken"/> that can be used to abort the operation.</param>
+        /// <returns>
+        /// A <see cref="Task"/> that can be used to monitor the asynchronous operation, whose result
+        /// returns the client applications corresponding to the specified redirect_uri.
+        /// </returns>
+        public virtual Task<TApplication[]> FindByRedirectUri(string address, CancellationToken cancellationToken)
+        {
+            return Store.FindByRedirectUri(address, cancellationToken);
         }
 
         /// <summary>
@@ -469,9 +483,8 @@ namespace OpenIddict.Core
             var address = await Store.GetRedirectUriAsync(application, cancellationToken);
             if (!string.IsNullOrEmpty(address))
             {
-                Uri uri;
                 // Ensure the redirect_uri is a valid and absolute URL.
-                if (!Uri.TryCreate(address, UriKind.Absolute, out uri))
+                if (!Uri.TryCreate(address, UriKind.Absolute, out Uri uri))
                 {
                     throw new ArgumentException("The redirect_uri must be an absolute URL.");
                 }
@@ -487,9 +500,8 @@ namespace OpenIddict.Core
             address = await Store.GetLogoutRedirectUriAsync(application, cancellationToken);
             if (!string.IsNullOrEmpty(address))
             {
-                Uri uri;
                 // Ensure the post_logout_redirect_uri is a valid and absolute URL.
-                if (!Uri.TryCreate(address, UriKind.Absolute, out uri))
+                if (!Uri.TryCreate(address, UriKind.Absolute, out Uri uri))
                 {
                     throw new ArgumentException("The post_logout_redirect_uri must be an absolute URL.");
                 }
@@ -502,6 +514,34 @@ namespace OpenIddict.Core
             }
         }
 
+        /// <summary>
+        /// Validates the specified post_logout_redirect_uri.
+        /// </summary>
+        /// <param name="address">The address that should be compared to the post_logout_redirect_uri stored in the database.</param>
+        /// <param name="cancellationToken">The <see cref="CancellationToken"/> that can be used to abort the operation.</param>
+        /// <returns>
+        /// A <see cref="Task"/> that can be used to monitor the asynchronous operation, whose result
+        /// returns a boolean indicating whether the post_logout_redirect_uri was valid.
+        /// </returns>
+        public virtual async Task<bool> ValidateLogoutRedirectUriAsync(string address, CancellationToken cancellationToken)
+        {
+            // Warning: SQL engines like Microsoft SQL Server are known to use case-insensitive lookups by default.
+            // To ensure a case-sensitive comparison is used, string.Equals(Ordinal) is manually called here.
+            foreach (var application in await Store.FindByLogoutRedirectUri(address, cancellationToken))
+            {
+                // Note: the post_logout_redirect_uri must be compared using case-sensitive "Simple String Comparison".
+                if (string.Equals(address, await Store.GetLogoutRedirectUriAsync(application, cancellationToken), StringComparison.Ordinal))
+                {
+                    return true;
+                }
+            }
+
+            Logger.LogWarning("Client validation failed because '{PostLogoutRedirectUri}' " +
+                              "was not a valid post_logout_redirect_uri.", address);
+
+            return false;
+        }
+
         /// <summary>
         /// Validates the redirect_uri associated with an application.
         /// </summary>
@@ -519,15 +559,17 @@ namespace OpenIddict.Core
                 throw new ArgumentNullException(nameof(application));
             }
 
-            if (!string.Equals(address, await Store.GetRedirectUriAsync(application, cancellationToken), StringComparison.Ordinal))
+            // Note: the redirect_uri must be compared using case-sensitive "Simple String Comparison".
+            // See http://openid.net/specs/openid-connect-core-1_0.html#AuthRequest for more information.
+            if (string.Equals(address, await Store.GetRedirectUriAsync(application, cancellationToken), StringComparison.Ordinal))
             {
-                Logger.LogWarning("Client validation failed because {RedirectUri} was not a valid redirect_uri " +
-                                  "for {Client}", address, await GetDisplayNameAsync(application, cancellationToken));
-
-                return false;
+                return true;
             }
 
-            return true;
+            Logger.LogWarning("Client validation failed because '{RedirectUri}' was not a valid redirect_uri " +
+                              "for '{Client}'.", address, await GetDisplayNameAsync(application, cancellationToken));
+
+            return false;
         }
 
         /// <summary>
diff --git a/src/OpenIddict.Core/Stores/IOpenIddictApplicationStore.cs b/src/OpenIddict.Core/Stores/IOpenIddictApplicationStore.cs
index 1a212ff0..972340bf 100644
--- a/src/OpenIddict.Core/Stores/IOpenIddictApplicationStore.cs
+++ b/src/OpenIddict.Core/Stores/IOpenIddictApplicationStore.cs
@@ -60,15 +60,26 @@ namespace OpenIddict.Core
         Task<TApplication> FindByClientIdAsync(string identifier, CancellationToken cancellationToken);
 
         /// <summary>
-        /// Retrieves an application using its post_logout_redirect_uri.
+        /// Retrieves all the applications associated with the specified post_logout_redirect_uri.
         /// </summary>
-        /// <param name="url">The post_logout_redirect_uri associated with the application.</param>
+        /// <param name="address">The post_logout_redirect_uri associated with the applications.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> that can be used to abort the operation.</param>
         /// <returns>
         /// A <see cref="Task"/> that can be used to monitor the asynchronous operation, whose result
-        /// returns the client application corresponding to the post_logout_redirect_uri.
+        /// returns the client applications corresponding to the specified post_logout_redirect_uri.
         /// </returns>
-        Task<TApplication> FindByLogoutRedirectUri(string url, CancellationToken cancellationToken);
+        Task<TApplication[]> FindByLogoutRedirectUri(string address, CancellationToken cancellationToken);
+
+        /// <summary>
+        /// Retrieves all the applications associated with the specified redirect_uri.
+        /// </summary>
+        /// <param name="address">The redirect_uri associated with the applications.</param>
+        /// <param name="cancellationToken">The <see cref="CancellationToken"/> that can be used to abort the operation.</param>
+        /// <returns>
+        /// A <see cref="Task"/> that can be used to monitor the asynchronous operation, whose result
+        /// returns the client applications corresponding to the specified redirect_uri.
+        /// </returns>
+        Task<TApplication[]> FindByRedirectUri(string address, CancellationToken cancellationToken);
 
         /// <summary>
         /// Retrieves the client identifier associated with an application.
diff --git a/src/OpenIddict.EntityFrameworkCore/Stores/OpenIddictApplicationStore.cs b/src/OpenIddict.EntityFrameworkCore/Stores/OpenIddictApplicationStore.cs
index 264489db..e6aaa966 100644
--- a/src/OpenIddict.EntityFrameworkCore/Stores/OpenIddictApplicationStore.cs
+++ b/src/OpenIddict.EntityFrameworkCore/Stores/OpenIddictApplicationStore.cs
@@ -156,17 +156,31 @@ namespace OpenIddict.EntityFrameworkCore
         }
 
         /// <summary>
-        /// Retrieves an application using its post_logout_redirect_uri.
+        /// Retrieves all the applications associated with the specified post_logout_redirect_uri.
         /// </summary>
-        /// <param name="url">The post_logout_redirect_uri associated with the application.</param>
+        /// <param name="address">The post_logout_redirect_uri associated with the applications.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> that can be used to abort the operation.</param>
         /// <returns>
         /// A <see cref="Task"/> that can be used to monitor the asynchronous operation, whose result
-        /// returns the client application corresponding to the post_logout_redirect_uri.
+        /// returns the client applications corresponding to the specified post_logout_redirect_uri.
         /// </returns>
-        public virtual Task<TApplication> FindByLogoutRedirectUri(string url, CancellationToken cancellationToken)
+        public virtual Task<TApplication[]> FindByLogoutRedirectUri(string address, CancellationToken cancellationToken)
         {
-            return Applications.SingleOrDefaultAsync(application => application.LogoutRedirectUri == url, cancellationToken);
+            return Applications.Where(application => application.LogoutRedirectUri == address).ToArrayAsync(cancellationToken);
+        }
+
+        /// <summary>
+        /// Retrieves all the applications associated with the specified redirect_uri.
+        /// </summary>
+        /// <param name="address">The redirect_uri associated with the applications.</param>
+        /// <param name="cancellationToken">The <see cref="CancellationToken"/> that can be used to abort the operation.</param>
+        /// <returns>
+        /// A <see cref="Task"/> that can be used to monitor the asynchronous operation, whose result
+        /// returns the client applications corresponding to the specified redirect_uri.
+        /// </returns>
+        public virtual Task<TApplication[]> FindByRedirectUri(string address, CancellationToken cancellationToken)
+        {
+            return Applications.Where(application => application.RedirectUri == address).ToArrayAsync(cancellationToken);
         }
 
         /// <summary>
diff --git a/src/OpenIddict/OpenIddictProvider.Session.cs b/src/OpenIddict/OpenIddictProvider.Session.cs
index 0dfc66c1..6eae960a 100644
--- a/src/OpenIddict/OpenIddictProvider.Session.cs
+++ b/src/OpenIddict/OpenIddictProvider.Session.cs
@@ -88,21 +88,17 @@ namespace OpenIddict
             var logger = context.HttpContext.RequestServices.GetRequiredService<ILogger<OpenIddictProvider<TApplication, TAuthorization, TScope, TToken>>>();
 
             // If an optional post_logout_redirect_uri was provided, validate it.
-            if (!string.IsNullOrEmpty(context.PostLogoutRedirectUri))
+            if (!string.IsNullOrEmpty(context.PostLogoutRedirectUri) &&
+                !await applications.ValidateLogoutRedirectUriAsync(context.PostLogoutRedirectUri, context.HttpContext.RequestAborted))
             {
-                var application = await applications.FindByLogoutRedirectUri(context.PostLogoutRedirectUri, context.HttpContext.RequestAborted);
-                if (application == null)
-                {
-                    logger.LogError("The logout request was rejected because the client application corresponding " +
-                                    "to the specified post_logout_redirect_uri was not found in the database: " +
-                                    "'{PostLogoutRedirectUri}'.", context.PostLogoutRedirectUri);
+                logger.LogError("The logout request was rejected because the specified post_logout_redirect_uri " +
+                                "was invalid: '{PostLogoutRedirectUri}'.", context.PostLogoutRedirectUri);
 
-                    context.Reject(
-                        error: OpenIdConnectConstants.Errors.InvalidClient,
-                        description: "Invalid post_logout_redirect_uri.");
+                context.Reject(
+                    error: OpenIdConnectConstants.Errors.InvalidClient,
+                    description: "Invalid post_logout_redirect_uri.");
 
-                    return;
-                }
+                return;
             }
 
             context.Validate();
diff --git a/test/OpenIddict.Tests/OpenIddictProviderTests.Session.cs b/test/OpenIddict.Tests/OpenIddictProviderTests.Session.cs
index 678a0972..c4c288d6 100644
--- a/test/OpenIddict.Tests/OpenIddictProviderTests.Session.cs
+++ b/test/OpenIddict.Tests/OpenIddictProviderTests.Session.cs
@@ -64,8 +64,8 @@ namespace OpenIddict.Tests
             // Arrange
             var manager = CreateApplicationManager(instance =>
             {
-                instance.Setup(mock => mock.FindByLogoutRedirectUri("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
-                    .ReturnsAsync(value: null);
+                instance.Setup(mock => mock.ValidateLogoutRedirectUriAsync("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
+                    .ReturnsAsync(false);
             });
 
             var server = CreateAuthorizationServer(builder =>
@@ -85,7 +85,7 @@ namespace OpenIddict.Tests
             Assert.Equal(OpenIdConnectConstants.Errors.InvalidClient, response.Error);
             Assert.Equal("Invalid post_logout_redirect_uri.", response.ErrorDescription);
 
-            Mock.Get(manager).Verify(mock => mock.FindByLogoutRedirectUri("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()), Times.Once());
+            Mock.Get(manager).Verify(mock => mock.ValidateLogoutRedirectUriAsync("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()), Times.Once());
         }
 
         [Fact]
@@ -98,10 +98,8 @@ namespace OpenIddict.Tests
             {
                 builder.Services.AddSingleton(CreateApplicationManager(instance =>
                 {
-                    var application = new OpenIddictApplication();
-
-                    instance.Setup(mock => mock.FindByLogoutRedirectUri("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
-                        .ReturnsAsync(application);
+                    instance.Setup(mock => mock.ValidateLogoutRedirectUriAsync("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
+                        .ReturnsAsync(true);
                 }));
 
                 builder.Services.AddSingleton(cache.Object);
@@ -137,10 +135,8 @@ namespace OpenIddict.Tests
             {
                 builder.Services.AddSingleton(CreateApplicationManager(instance =>
                 {
-                    var application = new OpenIddictApplication();
-
-                    instance.Setup(mock => mock.FindByLogoutRedirectUri("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
-                        .ReturnsAsync(application);
+                    instance.Setup(mock => mock.ValidateLogoutRedirectUriAsync("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
+                        .ReturnsAsync(true);
                 }));
             });
 
@@ -165,8 +161,8 @@ namespace OpenIddict.Tests
             {
                 builder.Services.AddSingleton(CreateApplicationManager(instance =>
                 {
-                    instance.Setup(mock => mock.FindByLogoutRedirectUri("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
-                        .ReturnsAsync(value: null);
+                    instance.Setup(mock => mock.ValidateLogoutRedirectUriAsync("http://www.fabrikam.com/path", It.IsAny<CancellationToken>()))
+                        .ReturnsAsync(false);
                 }));
 
                 builder.EnableAuthorizationEndpoint("/logout-status-code-middleware");