From e6c91a15721b4886a2b0c5e228cbbb17ee87b182 Mon Sep 17 00:00:00 2001
From: Ayaz Salikhov <mathbunnyru@users.noreply.github.com>
Date: Thu, 20 Aug 2026 15:57:56 +0100
Subject: [PATCH] fix: Use credentialTypeValidator in LedgerEntry (#3185)

---
 src/rpc/common/Validators.hpp    |  3 ++-
 src/rpc/handlers/LedgerEntry.cpp | 17 +++++++++++------
 src/rpc/handlers/LedgerEntry.hpp |  1 +
 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/rpc/common/Validators.hpp b/src/rpc/common/Validators.hpp
index 5c5cccbc3..ee9527b51 100644
--- a/src/rpc/common/Validators.hpp
+++ b/src/rpc/common/Validators.hpp
@@ -590,7 +590,8 @@ struct CustomValidators final {
     /**
      * @brief Provides a validator for validating credential_type.
      *
-     * Used by AuthorizeCredentialValidator in deposit_preauth.
+     * Used by AuthorizeCredentialValidator in deposit_preauth and by the credential
+     * object lookup in ledger_entry.
      */
     static CustomValidator credentialTypeValidator;
 };
diff --git a/src/rpc/handlers/LedgerEntry.cpp b/src/rpc/handlers/LedgerEntry.cpp
index 20982b628..bef9c8666 100644
--- a/src/rpc/handlers/LedgerEntry.cpp
+++ b/src/rpc/handlers/LedgerEntry.cpp
@@ -13,6 +13,7 @@
 #include <boost/json/object.hpp>
 #include <boost/json/value.hpp>
 #include <boost/json/value_to.hpp>
+#include <xrpl/basics/Blob.h>
 #include <xrpl/basics/Slice.h>
 #include <xrpl/basics/StringUtilities.h>
 #include <xrpl/basics/base_uint.h>
@@ -32,6 +33,7 @@
 
 #include <algorithm>
 #include <cstdint>
+#include <optional>
 #include <string>
 #include <string_view>
 #include <unordered_map>
@@ -422,20 +424,23 @@ tag_invoke(boost::json::value_to_tag<LedgerEntryHandler::Input>, boost::json::va
         return xrpl::keylet::oracle(*account, documentId).key;
     };
 
-    auto const parseCredentialFromJson = [](boost::json::value const& json) {
+    auto const parseCredentialFromJson =
+        [](boost::json::value const& json) -> std::optional<xrpl::uint256> {
         auto const subject = util::parseBase58Wrapper<xrpl::AccountID>(
             boost::json::value_to<std::string>(json.at(JS(subject)))
         );
         auto const issuer = util::parseBase58Wrapper<xrpl::AccountID>(
             boost::json::value_to<std::string>(json.at(JS(issuer)))
         );
-        auto const credType =
+        auto const credTypeOpt =
             xrpl::strUnHex(boost::json::value_to<std::string>(json.at(JS(credential_type))));
 
-        return xrpl::keylet::credential(
-                   *subject, *issuer, xrpl::Slice(credType->data(), credType->size())
-        )
-            .key;
+        return credTypeOpt.transform([&](xrpl::Blob const& credType) -> xrpl::uint256 {
+            return xrpl::keylet::credential(
+                       *subject, *issuer, xrpl::Slice(credType.data(), credType.size())
+            )
+                .key;
+        });
     };
 
     auto const indexFieldType =
diff --git a/src/rpc/handlers/LedgerEntry.hpp b/src/rpc/handlers/LedgerEntry.hpp
index 8c5b0702e..ea32d9450 100644
--- a/src/rpc/handlers/LedgerEntry.hpp
+++ b/src/rpc/handlers/LedgerEntry.hpp
@@ -380,6 +380,7 @@ public:
                      meta::WithCustomError{
                          validation::Type<std::string>{}, Status(ClioError::RpcMalformedRequest)
                      },
+                     validation::CustomValidators::credentialTypeValidator,
                  },
              }}},
             {JS(mpt_issuance),