diff --git a/src/libxrpl/protocol/SField.cpp b/src/libxrpl/protocol/SField.cpp
index 18226008504..537fa557fcc 100644
--- a/src/libxrpl/protocol/SField.cpp
+++ b/src/libxrpl/protocol/SField.cpp
@@ -72,7 +72,10 @@ TypedField<T>::TypedField(private_access_tag_t pat, Args&&... args)
 // SFields which, for historical reasons, do not follow naming conventions.
 SField const sfInvalid(access, -1);
 SField const sfGeneric(access, 0);
+// The following two fields aren't used anywhere, but they break tests/have
+// downstream effects.
 SField const sfHash(access, STI_UINT256, 257, "hash");
+SField const sfIndex(access, STI_UINT256, 258, "index");
 
 #include <xrpl/protocol/detail/sfields.macro>
 
diff --git a/src/test/rpc/LedgerRPC_test.cpp b/src/test/rpc/LedgerRPC_test.cpp
index c5e10198c49..41657468666 100644
--- a/src/test/rpc/LedgerRPC_test.cpp
+++ b/src/test/rpc/LedgerRPC_test.cpp
@@ -26,6 +26,7 @@
 #include <xrpld/app/misc/TxQ.h>
 #include <xrpl/basics/StringUtilities.h>
 #include <xrpl/beast/unit_test.h>
+#include <xrpl/json/json_value.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/STXChainBridge.h>
@@ -1207,6 +1208,42 @@ class LedgerRPC_test : public beast::unit_test::suite
             checkErrorValue(jrr[jss::result], "malformedRequest", "");
         }
 
+        {
+            // Failed, authorized_credentials contains string data
+            Json::Value jvParams;
+            jvParams[jss::ledger_index] = jss::validated;
+            jvParams[jss::deposit_preauth][jss::owner] = bob.human();
+            jvParams[jss::deposit_preauth][jss::authorized_credentials] =
+                Json::arrayValue;
+            auto& arr(
+                jvParams[jss::deposit_preauth][jss::authorized_credentials]);
+            arr.append("foobar");
+
+            auto const jrr =
+                env.rpc("json", "ledger_entry", to_string(jvParams));
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
+        }
+
+        {
+            // Failed, authorized_credentials contains arrays
+            Json::Value jvParams;
+            jvParams[jss::ledger_index] = jss::validated;
+            jvParams[jss::deposit_preauth][jss::owner] = bob.human();
+            jvParams[jss::deposit_preauth][jss::authorized_credentials] =
+                Json::arrayValue;
+            auto& arr(
+                jvParams[jss::deposit_preauth][jss::authorized_credentials]);
+            Json::Value payload = Json::arrayValue;
+            payload.append(42);
+            arr.append(std::move(payload));
+
+            auto const jrr =
+                env.rpc("json", "ledger_entry", to_string(jvParams));
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
+        }
+
         {
             // Failed, authorized_credentials is empty array
             Json::Value jvParams;
@@ -1263,6 +1300,27 @@ class LedgerRPC_test : public beast::unit_test::suite
                 jrr[jss::result], "malformedAuthorizedCredentials", "");
         }
 
+        {
+            // Failed, issuer is not set
+            Json::Value jvParams;
+            jvParams[jss::ledger_index] = jss::validated;
+            jvParams[jss::deposit_preauth][jss::owner] = bob.human();
+
+            jvParams[jss::deposit_preauth][jss::authorized_credentials] =
+                Json::arrayValue;
+            auto& arr(
+                jvParams[jss::deposit_preauth][jss::authorized_credentials]);
+
+            Json::Value jo;
+            jo[jss::credential_type] = strHex(std::string_view(credType));
+            arr.append(std::move(jo));
+
+            auto const jrr =
+                env.rpc("json", "ledger_entry", to_string(jvParams));
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
+        }
+
         {
             // Failed, issuer isn't string
             Json::Value jvParams;
@@ -1285,6 +1343,30 @@ class LedgerRPC_test : public beast::unit_test::suite
                 jrr[jss::result], "malformedAuthorizedCredentials", "");
         }
 
+        {
+            // Failed, issuer is an array
+            Json::Value jvParams;
+            jvParams[jss::ledger_index] = jss::validated;
+            jvParams[jss::deposit_preauth][jss::owner] = bob.human();
+
+            jvParams[jss::deposit_preauth][jss::authorized_credentials] =
+                Json::arrayValue;
+            auto& arr(
+                jvParams[jss::deposit_preauth][jss::authorized_credentials]);
+
+            Json::Value jo;
+            Json::Value payload = Json::arrayValue;
+            payload.append(42);
+            jo[jss::issuer] = std::move(payload);
+            jo[jss::credential_type] = strHex(std::string_view(credType));
+            arr.append(std::move(jo));
+
+            auto const jrr =
+                env.rpc("json", "ledger_entry", to_string(jvParams));
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
+        }
+
         {
             // Failed, issuer isn't valid encoded account
             Json::Value jvParams;
@@ -1307,12 +1389,32 @@ class LedgerRPC_test : public beast::unit_test::suite
                 jrr[jss::result], "malformedAuthorizedCredentials", "");
         }
 
+        {
+            // Failed, credential_type is not set
+            Json::Value jvParams;
+            jvParams[jss::ledger_index] = jss::validated;
+            jvParams[jss::deposit_preauth][jss::owner] = bob.human();
+
+            jvParams[jss::deposit_preauth][jss::authorized_credentials] =
+                Json::arrayValue;
+            auto& arr(
+                jvParams[jss::deposit_preauth][jss::authorized_credentials]);
+
+            Json::Value jo;
+            jo[jss::issuer] = issuer.human();
+            arr.append(std::move(jo));
+
+            auto const jrr =
+                env.rpc("json", "ledger_entry", to_string(jvParams));
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
+        }
+
         {
             // Failed, credential_type isn't string
             Json::Value jvParams;
             jvParams[jss::ledger_index] = jss::validated;
             jvParams[jss::deposit_preauth][jss::owner] = bob.human();
-            jvParams[jss::deposit_preauth][jss::authorized] = alice.human();
 
             jvParams[jss::deposit_preauth][jss::authorized_credentials] =
                 Json::arrayValue;
@@ -1326,7 +1428,32 @@ class LedgerRPC_test : public beast::unit_test::suite
 
             auto const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams));
-            checkErrorValue(jrr[jss::result], "malformedRequest", "");
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
+        }
+
+        {
+            // Failed, credential_type is an array
+            Json::Value jvParams;
+            jvParams[jss::ledger_index] = jss::validated;
+            jvParams[jss::deposit_preauth][jss::owner] = bob.human();
+
+            jvParams[jss::deposit_preauth][jss::authorized_credentials] =
+                Json::arrayValue;
+            auto& arr(
+                jvParams[jss::deposit_preauth][jss::authorized_credentials]);
+
+            Json::Value jo;
+            jo[jss::issuer] = issuer.human();
+            Json::Value payload = Json::arrayValue;
+            payload.append(42);
+            jo[jss::credential_type] = std::move(payload);
+            arr.append(std::move(jo));
+
+            auto const jrr =
+                env.rpc("json", "ledger_entry", to_string(jvParams));
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
         }
 
         {
@@ -1334,7 +1461,6 @@ class LedgerRPC_test : public beast::unit_test::suite
             Json::Value jvParams;
             jvParams[jss::ledger_index] = jss::validated;
             jvParams[jss::deposit_preauth][jss::owner] = bob.human();
-            jvParams[jss::deposit_preauth][jss::authorized] = alice.human();
 
             jvParams[jss::deposit_preauth][jss::authorized_credentials] =
                 Json::arrayValue;
@@ -1348,7 +1474,8 @@ class LedgerRPC_test : public beast::unit_test::suite
 
             auto const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams));
-            checkErrorValue(jrr[jss::result], "malformedRequest", "");
+            checkErrorValue(
+                jrr[jss::result], "malformedAuthorizedCredentials", "");
         }
     }
 
diff --git a/src/test/rpc/ServerInfo_test.cpp b/src/test/rpc/ServerInfo_test.cpp
index fbeb4220d16..e6f889c5bdf 100644
--- a/src/test/rpc/ServerInfo_test.cpp
+++ b/src/test/rpc/ServerInfo_test.cpp
@@ -198,6 +198,28 @@ admin = 127.0.0.1
             BEAST_EXPECT(
                 result[jss::result][jss::TYPES]["AccountID"].asUInt() == 8);
 
+            // check exception SFields
+            {
+                auto const fieldExists = [&](std::string name) {
+                    for (auto& field : result[jss::result][jss::FIELDS])
+                    {
+                        if (field[0u].asString() == name)
+                        {
+                            return true;
+                        }
+                    }
+                    return false;
+                };
+                BEAST_EXPECT(fieldExists("Generic"));
+                BEAST_EXPECT(fieldExists("Invalid"));
+                BEAST_EXPECT(fieldExists("ObjectEndMarker"));
+                BEAST_EXPECT(fieldExists("ArrayEndMarker"));
+                BEAST_EXPECT(fieldExists("taker_gets_funded"));
+                BEAST_EXPECT(fieldExists("taker_pays_funded"));
+                BEAST_EXPECT(fieldExists("hash"));
+                BEAST_EXPECT(fieldExists("index"));
+            }
+
             // test that base_uint types are replaced with "Hash" prefix
             {
                 auto const types = result[jss::result][jss::TYPES];
diff --git a/src/xrpld/rpc/handlers/LedgerEntry.cpp b/src/xrpld/rpc/handlers/LedgerEntry.cpp
index 6a3b7a48686..5d03bbb189d 100644
--- a/src/xrpld/rpc/handlers/LedgerEntry.cpp
+++ b/src/xrpld/rpc/handlers/LedgerEntry.cpp
@@ -41,6 +41,12 @@ parseAuthorizeCredentials(Json::Value const& jv)
     STArray arr(sfAuthorizeCredentials, jv.size());
     for (auto const& jo : jv)
     {
+        if (!jo.isObject() ||  //
+            !jo.isMember(jss::issuer) || !jo[jss::issuer].isString() ||
+            !jo.isMember(jss::credential_type) ||
+            !jo[jss::credential_type].isString())
+            return {};
+
         auto const issuer = parseBase58<AccountID>(jo[jss::issuer].asString());
         if (!issuer || !*issuer)
             return {};