diff --git a/src/libraries/Common/src/Interop/OSX/System.Security.Cryptography.Native.Apple/Interop.SecKeyRef.cs b/src/libraries/Common/src/Interop/OSX/System.Security.Cryptography.Native.Apple/Interop.SecKeyRef.cs
index ad5a34517b1a..b9ce7b498ef6 100644
--- a/src/libraries/Common/src/Interop/OSX/System.Security.Cryptography.Native.Apple/Interop.SecKeyRef.cs
+++ b/src/libraries/Common/src/Interop/OSX/System.Security.Cryptography.Native.Apple/Interop.SecKeyRef.cs
@@ -127,6 +127,10 @@ internal static int GetSimpleKeySizeInBits(SafeSecKeyRefHandle publicKey)
         {
             const int errSecPassphraseRequired = -25260;
 
+            // macOS Sonoma 14.4 started returning errSecInvalidKeyAttributeMask when a key could not be exported
+            // because it must be exported with a password.
+            const int errSecInvalidKeyAttributeMask = -67738;
+
             int result = AppleCryptoNative_SecKeyCopyExternalRepresentation(
                 key,
                 out SafeCFDataHandle data,
@@ -141,7 +145,7 @@ internal static int GetSimpleKeySizeInBits(SafeSecKeyRefHandle publicKey)
                         externalRepresentation = CoreFoundation.CFGetData(data);
                         return true;
                     case kErrorSeeError:
-                        if (Interop.CoreFoundation.GetErrorCode(errorHandle) == errSecPassphraseRequired)
+                        if (Interop.CoreFoundation.GetErrorCode(errorHandle) is errSecPassphraseRequired or errSecInvalidKeyAttributeMask)
                         {
                             externalRepresentation = Array.Empty<byte>();
                             return false;
diff --git a/src/libraries/System.Security.Cryptography.X509Certificates/tests/CertTests.cs b/src/libraries/System.Security.Cryptography.X509Certificates/tests/CertTests.cs
index 439252e588c0..15e9be90ae1f 100644
--- a/src/libraries/System.Security.Cryptography.X509Certificates/tests/CertTests.cs
+++ b/src/libraries/System.Security.Cryptography.X509Certificates/tests/CertTests.cs
@@ -4,6 +4,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Runtime.InteropServices;
+using System.Security.Cryptography.X509Certificates.Tests.CertificateCreation;
 using System.Threading;
 using Microsoft.DotNet.XUnitExtensions;
 using Test.Cryptography;
@@ -24,6 +25,108 @@ public CertTests(ITestOutputHelper output)
             _log = output;
         }
 
+        [Fact]
+        public static void PrivateKey_FromCertificate_CanExportPrivate_ECDsa()
+        {
+            using (ECDsa ca = ECDsa.Create(ECCurve.NamedCurves.nistP256))
+            {
+                CertificateRequest req = new("CN=potatos", ca, HashAlgorithmName.SHA256);
+
+                using (X509Certificate2 cert = req.CreateSelfSigned(DateTimeOffset.Now, DateTimeOffset.Now.AddDays(3)))
+                using (ECDsa certKey = cert.GetECDsaPrivateKey())
+                {
+                    ECParameters certParameters = certKey.ExportParameters(true);
+                    ECParameters originalParameters = ca.ExportParameters(true);
+                    AssertExtensions.SequenceEqual(originalParameters.D, certParameters.D);
+                }
+            }
+        }
+
+        [Fact]
+        public static void PrivateKey_FromCertificate_CanExportPrivate_RSA()
+        {
+            using (RSA ca = RSA.Create(2048))
+            {
+                CertificateRequest req = new("CN=potatos", ca, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
+
+                using (X509Certificate2 cert = req.CreateSelfSigned(DateTimeOffset.Now, DateTimeOffset.Now.AddDays(3)))
+                using (RSA certKey = cert.GetRSAPrivateKey())
+                {
+                    RSAParameters certParameters = certKey.ExportParameters(true);
+                    RSAParameters originalParameters = ca.ExportParameters(true);
+                    AssertExtensions.SequenceEqual(originalParameters.P, certParameters.P);
+                    AssertExtensions.SequenceEqual(originalParameters.Q, certParameters.Q);
+                }
+            }
+        }
+
+        [Fact]
+        [SkipOnPlatform(PlatformSupport.MobileAppleCrypto, "DSA is not available")]
+        public static void PrivateKey_FromCertificate_CanExportPrivate_DSA()
+        {
+            DSAParameters originalParameters = TestData.GetDSA1024Params();
+
+            using (DSA ca = DSA.Create())
+            {
+                ca.ImportParameters(originalParameters);
+                DSAX509SignatureGenerator gen = new DSAX509SignatureGenerator(ca);
+                X500DistinguishedName dn = new X500DistinguishedName("CN=potatos");
+
+                CertificateRequest req = new CertificateRequest(
+                    dn,
+                    gen.PublicKey,
+                    HashAlgorithmName.SHA1);
+
+                using (X509Certificate2 cert = req.Create(dn, gen, DateTimeOffset.Now, DateTimeOffset.Now.AddDays(3), new byte[] { 1, 2, 3 }))
+                using (X509Certificate2 certWithKey = cert.CopyWithPrivateKey(ca))
+                using (DSA certKey = certWithKey.GetDSAPrivateKey())
+                {
+                    DSAParameters certParameters = certKey.ExportParameters(true);
+                    AssertExtensions.SequenceEqual(originalParameters.X, certParameters.X);
+                }
+            }
+        }
+
+        [Fact]
+        public static void PrivateKey_FromCertificate_CanExportPrivate_ECDiffieHellman()
+        {
+            using (ECDsa ca = ECDsa.Create(ECCurve.NamedCurves.nistP256))
+            using (ECDiffieHellman ecdh = ECDiffieHellman.Create(ECCurve.NamedCurves.nistP256))
+            {
+                CertificateRequest issuerRequest = new CertificateRequest(
+                    new X500DistinguishedName("CN=root"),
+                    ca,
+                    HashAlgorithmName.SHA256);
+
+                issuerRequest.CertificateExtensions.Add(
+                    new X509BasicConstraintsExtension(true, false, 0, true));
+
+                CertificateRequest request = new CertificateRequest(
+                    new X500DistinguishedName("CN=potato"),
+                    new PublicKey(ecdh),
+                    HashAlgorithmName.SHA256);
+
+                request.CertificateExtensions.Add(
+                    new X509BasicConstraintsExtension(false, false, 0, true));
+                request.CertificateExtensions.Add(
+                    new X509KeyUsageExtension(X509KeyUsageFlags.KeyAgreement, true));
+
+                DateTimeOffset notBefore = DateTimeOffset.UtcNow;
+                DateTimeOffset notAfter = notBefore.AddDays(30);
+                byte[] serial = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };
+
+                using (X509Certificate2 issuer = issuerRequest.CreateSelfSigned(notBefore, notAfter))
+                using (X509Certificate2 cert = request.Create(issuer, notBefore, notAfter, serial))
+                using (X509Certificate2 certWithKey = cert.CopyWithPrivateKey(ecdh))
+                using (ECDiffieHellman certKey = certWithKey.GetECDiffieHellmanPrivateKey())
+                {
+                    ECParameters certParameters = certKey.ExportParameters(true);
+                    ECParameters originalParameters = ecdh.ExportParameters(true);
+                    AssertExtensions.SequenceEqual(originalParameters.D, certParameters.D);
+                }
+            }
+        }
+
         [Fact]
         public static void RaceUseAndDisposeDoesNotCrash()
         {
@@ -79,7 +182,7 @@ public static void X509CertTest()
                 // GetSerialNumber() returns in little-endian order.
                 Array.Reverse(expectedSerial);
                 AssertExtensions.SequenceEqual(expectedSerial, serial1);
-                
+
                 Assert.Equal("1.2.840.113549.1.1.1", cert.GetKeyAlgorithm());
 
                 int pklen = cert.GetPublicKey().Length;