diff --git a/src/Middleware/HttpOverrides/src/ForwardedHeadersOptions.cs b/src/Middleware/HttpOverrides/src/ForwardedHeadersOptions.cs
index ceb8ab32b997..cd49867fec1e 100644
--- a/src/Middleware/HttpOverrides/src/ForwardedHeadersOptions.cs
+++ b/src/Middleware/HttpOverrides/src/ForwardedHeadersOptions.cs
@@ -3,6 +3,7 @@
 
 using Microsoft.AspNetCore.HttpOverrides;
 using IPAddress = System.Net.IPAddress;
+using IPNetwork = System.Net.IPNetwork;
 
 namespace Microsoft.AspNetCore.Builder;
 
diff --git a/src/Middleware/HttpOverrides/src/IPNetwork.cs b/src/Middleware/HttpOverrides/src/IPNetwork.cs
index 9888de2d1535..7e0da19c040c 100644
--- a/src/Middleware/HttpOverrides/src/IPNetwork.cs
+++ b/src/Middleware/HttpOverrides/src/IPNetwork.cs
@@ -3,204 +3,60 @@
 
 using System.Diagnostics.CodeAnalysis;
 using System.Net;
-using System.Net.Sockets;
 
 namespace Microsoft.AspNetCore.HttpOverrides;
 
 /// <summary>
 /// A representation of an IP network based on CIDR notation.
 /// </summary>
+[System.Obsolete("Please use System.Net.IPNetwork instead")]
 public class IPNetwork
 {
+    private readonly System.Net.IPNetwork _network;
+
     /// <summary>
     /// Create a new <see cref="IPNetwork"/> with the specified <see cref="IPAddress"/> and prefix length.
     /// </summary>
     /// <param name="prefix">The <see cref="IPAddress"/>.</param>
     /// <param name="prefixLength">The prefix length.</param>
     /// <exception cref="ArgumentOutOfRangeException"><paramref name="prefixLength"/> is out of range.</exception>
-    public IPNetwork(IPAddress prefix, int prefixLength) : this(prefix, prefixLength, true)
+    public IPNetwork(IPAddress prefix, int prefixLength)
     {
+        _network = new(prefix, prefixLength);
     }
 
-    private IPNetwork(IPAddress prefix, int prefixLength, bool checkPrefixLengthRange)
-    {
-        if (checkPrefixLengthRange &&
-            !IsValidPrefixLengthRange(prefix, prefixLength))
-        {
-            throw new ArgumentOutOfRangeException(nameof(prefixLength), "The prefix length was out of range.");
-        }
-
-        Prefix = prefix;
-        PrefixLength = prefixLength;
-        PrefixBytes = Prefix.GetAddressBytes();
-        Mask = CreateMask();
-    }
+    private IPNetwork(System.Net.IPNetwork network) => _network = network;
 
     /// <summary>
     /// Get the <see cref="IPAddress"/> that represents the prefix for the network.
     /// </summary>
-    public IPAddress Prefix { get; }
-
-    private byte[] PrefixBytes { get; }
+    public IPAddress Prefix => _network.BaseAddress;
 
     /// <summary>
     /// The CIDR notation of the subnet mask
     /// </summary>
-    public int PrefixLength { get; }
-
-    private byte[] Mask { get; }
+    public int PrefixLength => _network.PrefixLength;
 
     /// <summary>
     /// Determine whether a given The <see cref="IPAddress"/> is part of the IP network.
     /// </summary>
     /// <param name="address">The <see cref="IPAddress"/>.</param>
     /// <returns><see langword="true"/> if the <see cref="IPAddress"/> is part of the IP network. Otherwise, <see langword="false"/>.</returns>
-    public bool Contains(IPAddress address)
-    {
-        if (Prefix.AddressFamily != address.AddressFamily)
-        {
-            return false;
-        }
-
-        var addressBytes = address.GetAddressBytes();
-        for (int i = 0; i < PrefixBytes.Length && Mask[i] != 0; i++)
-        {
-            if ((PrefixBytes[i] & Mask[i]) != (addressBytes[i] & Mask[i]))
-            {
-                return false;
-            }
-        }
-
-        return true;
-    }
-
-    private byte[] CreateMask()
-    {
-        var mask = new byte[PrefixBytes.Length];
-        int remainingBits = PrefixLength;
-        int i = 0;
-        while (remainingBits >= 8)
-        {
-            mask[i] = 0xFF;
-            i++;
-            remainingBits -= 8;
-        }
-        if (remainingBits > 0)
-        {
-            mask[i] = (byte)(0xFF << (8 - remainingBits));
-        }
-
-        return mask;
-    }
-
-    private static bool IsValidPrefixLengthRange(IPAddress prefix, int prefixLength)
-    {
-        if (prefixLength < 0)
-        {
-            return false;
-        }
-
-        return prefix.AddressFamily switch
-        {
-            AddressFamily.InterNetwork => prefixLength <= 32,
-            AddressFamily.InterNetworkV6 => prefixLength <= 128,
-            _ => true
-        };
-    }
+    public bool Contains(IPAddress address) => _network.Contains(address);
 
-    /// <summary>
-    /// Converts the specified <see cref="ReadOnlySpan{T}"/> of <see langword="char"/> representation of
-    /// an IP address and a prefix length to its <see cref="IPNetwork"/> equivalent.
-    /// </summary>
-    /// <param name="networkSpan">The <see cref="ReadOnlySpan{T}"/> of <see langword="char"/> to convert, in CIDR notation.</param>
-    /// <returns>
-    ///The <see cref="IPNetwork"/> equivalent to the IP address and prefix length contained in <paramref name="networkSpan"/>.
-    /// </returns>
-    /// <exception cref="FormatException"><paramref name="networkSpan"/> is not in the correct format.</exception>
-    /// <exception cref="ArgumentOutOfRangeException">The prefix length contained in <paramref name="networkSpan"/> is out of range.</exception>
-    /// <inheritdoc cref="TryParseComponents(ReadOnlySpan{char}, out IPAddress?, out int)"/>
-    public static IPNetwork Parse(ReadOnlySpan<char> networkSpan)
-    {
-        if (!TryParseComponents(networkSpan, out var prefix, out var prefixLength))
-        {
-            throw new FormatException("An invalid IP address or prefix length was specified.");
-        }
-
-        if (!IsValidPrefixLengthRange(prefix, prefixLength))
-        {
-            throw new ArgumentOutOfRangeException(nameof(networkSpan), "The prefix length was out of range.");
-        }
+    /// <inheritdoc cref="System.Net.IPNetwork.Parse(ReadOnlySpan{char})"/>
+    public static IPNetwork Parse(ReadOnlySpan<char> networkSpan) => new(System.Net.IPNetwork.Parse(networkSpan));
 
-        return new IPNetwork(prefix, prefixLength, false);
-    }
-
-    /// <summary>
-    /// Converts the specified <see cref="ReadOnlySpan{T}"/> of <see langword="char"/> representation of
-    /// an IP address and a prefix length to its <see cref="IPNetwork"/> equivalent, and returns a value
-    /// that indicates whether the conversion succeeded.
-    /// </summary>
-    /// <param name="networkSpan">The <see cref="ReadOnlySpan{T}"/> of <see langword="char"/> to validate.</param>
-    /// <param name="network">
-    /// When this method returns, contains the <see cref="IPNetwork"/> equivalent to the IP Address
-    /// and prefix length contained in <paramref name="networkSpan"/>, if the conversion succeeded,
-    /// or <see langword="null"/> if the conversion failed. This parameter is passed uninitialized.
-    /// </param>
-    /// <returns>
-    /// <see langword="true"/> if the <paramref name="networkSpan"/> parameter was
-    /// converted successfully; otherwise <see langword="false"/>.
-    /// </returns>
-    /// <inheritdoc cref="TryParseComponents(ReadOnlySpan{char}, out IPAddress?, out int)"/>
+    /// <inheritdoc cref="System.Net.IPNetwork.TryParse(ReadOnlySpan{char}, out System.Net.IPNetwork)"/>
     public static bool TryParse(ReadOnlySpan<char> networkSpan, [NotNullWhen(true)] out IPNetwork? network)
     {
-        network = null;
-
-        if (!TryParseComponents(networkSpan, out var prefix, out var prefixLength))
+        if (System.Net.IPNetwork.TryParse(networkSpan, out var ipNetwork))
         {
-            return false;
+            network = new(ipNetwork);
+            return true;
         }
 
-        if (!IsValidPrefixLengthRange(prefix, prefixLength))
-        {
-            return false;
-        }
-
-        network = new IPNetwork(prefix, prefixLength, false);
-        return true;
-    }
-
-    /// <remarks>
-    /// <para>
-    /// The specified representation must be expressed using CIDR (Classless Inter-Domain Routing) notation, or 'slash notation',
-    /// which contains an IPv4 or IPv6 address and the subnet mask prefix length, separated by a forward slash.
-    /// </para>
-    /// <example>
-    /// e.g. <c>"192.168.0.1/31"</c> for IPv4, <c>"2001:db8:3c4d::1/127"</c> for IPv6
-    /// </example>
-    /// </remarks>
-    private static bool TryParseComponents(
-        ReadOnlySpan<char> networkSpan,
-        [NotNullWhen(true)] out IPAddress? prefix,
-        out int prefixLength)
-    {
-        prefix = null;
-        prefixLength = default;
-
-        var forwardSlashIndex = networkSpan.IndexOf('/');
-        if (forwardSlashIndex < 0)
-        {
-            return false;
-        }
-
-        if (!IPAddress.TryParse(networkSpan.Slice(0, forwardSlashIndex), out prefix))
-        {
-            return false;
-        }
-
-        if (!int.TryParse(networkSpan.Slice(forwardSlashIndex + 1), out prefixLength))
-        {
-            return false;
-        }
-
-        return true;
+        network = null;
+        return false;
     }
 }
diff --git a/src/Middleware/HttpOverrides/src/PublicAPI.Unshipped.txt b/src/Middleware/HttpOverrides/src/PublicAPI.Unshipped.txt
index 7dc5c58110bf..a8a1a579461f 100644
--- a/src/Middleware/HttpOverrides/src/PublicAPI.Unshipped.txt
+++ b/src/Middleware/HttpOverrides/src/PublicAPI.Unshipped.txt
@@ -1 +1,3 @@
 #nullable enable
+*REMOVED*Microsoft.AspNetCore.Builder.ForwardedHeadersOptions.KnownNetworks.get -> System.Collections.Generic.IList<Microsoft.AspNetCore.HttpOverrides.IPNetwork!>!
+Microsoft.AspNetCore.Builder.ForwardedHeadersOptions.KnownNetworks.get -> System.Collections.Generic.IList<System.Net.IPNetwork>!
diff --git a/src/Middleware/HttpOverrides/test/ForwardedHeadersMiddlewareTest.cs b/src/Middleware/HttpOverrides/test/ForwardedHeadersMiddlewareTest.cs
index 4fd1341acc45..69dc2e6dd9aa 100644
--- a/src/Middleware/HttpOverrides/test/ForwardedHeadersMiddlewareTest.cs
+++ b/src/Middleware/HttpOverrides/test/ForwardedHeadersMiddlewareTest.cs
@@ -1092,7 +1092,7 @@ public async Task XForwardForIPv4ToIPv6Mapping(string forHeader, string knownPro
             var knownNetworkParts = knownNetwork.Split('/');
             var networkIp = IPAddress.Parse(knownNetworkParts[0]);
             var prefixLength = int.Parse(knownNetworkParts[1], CultureInfo.InvariantCulture);
-            options.KnownNetworks.Add(new IPNetwork(networkIp, prefixLength));
+            options.KnownNetworks.Add(new System.Net.IPNetwork(networkIp, prefixLength));
         }
 
         using var host = new HostBuilder()
diff --git a/src/Middleware/HttpOverrides/test/IPNetworkTest.cs b/src/Middleware/HttpOverrides/test/IPNetworkTest.cs
index c8f33f7a333b..9538f121c550 100644
--- a/src/Middleware/HttpOverrides/test/IPNetworkTest.cs
+++ b/src/Middleware/HttpOverrides/test/IPNetworkTest.cs
@@ -4,6 +4,7 @@
 
 namespace Microsoft.AspNetCore.HttpOverrides;
 
+[System.Obsolete]
 public class IPNetworkTest
 {
     [Theory]