diff --git a/libethereum/Precompiled.cpp b/libethereum/Precompiled.cpp
index 339829186..fbc2be280 100644
--- a/libethereum/Precompiled.cpp
+++ b/libethereum/Precompiled.cpp
@@ -251,10 +251,16 @@ static Logger& getLogger( int a_severity = VerbosityTrace ) {
 
 static void convertBytesToString(
     bytesConstRef _in, size_t _startPosition, std::string& _out, size_t& _stringLength ) {
+    if ( _in.size() < UINT256_SIZE ) {
+        throw std::runtime_error( "Input is too short - invalid input in convertBytesToString()" );
+    }
     bigint const sstringLength( parseBigEndianRightPadded( _in, _startPosition, UINT256_SIZE ) );
     _stringLength = sstringLength.convert_to< size_t >();
+    if ( _startPosition + UINT256_SIZE + _stringLength > _in.size() ) {
+        throw std::runtime_error( "Invalid input in convertBytesToString()" );
+    }
     vector_ref< const unsigned char > byteFilename =
-        _in.cropped( _startPosition + 32, _stringLength );
+        _in.cropped( _startPosition + UINT256_SIZE, _stringLength );
     _out = std::string( ( char* ) byteFilename.data(), _stringLength );
 }
 
@@ -753,7 +759,6 @@ static std::pair< std::string, unsigned > parseHistoricFieldRequest( std::string
     // first 3 elements are skaleConfig, sChain, nodes - it was checked before
     unsigned id = std::stoul( splitted.at( 3 ) );
     std::string fieldName;
-    boost::trim_if( splitted.at( 4 ), []( char c ) { return c == '\0'; } );
     std::set< std::string > allowedValues{ "id", "schainIndex", "owner" };
     fieldName = splitted.at( 4 );
     if ( allowedValues.count( fieldName ) ) {
@@ -782,7 +787,7 @@ static std::pair< std::string, unsigned > parseHistoricFieldRequest( std::string
  * to request the value for 1-st node (1 based) for the node id field the input should be
  * input=skaleConfig.sChain.nodes.0.id (inside skaled node indexes are 0 based)
  * so one should pass the following as calldata:
- * toBytes( ( ( input.length + 1 ) / 32 ) * 32) + toBytes(input)
+ * toBytes( input.length + toBytes(input) )
  */
 ETH_REGISTER_PRECOMPILED( getConfigVariableUint256 )( bytesConstRef _in ) {
     try {
@@ -855,8 +860,7 @@ ETH_REGISTER_PRECOMPILED( getConfigVariableUint256 )( bytesConstRef _in ) {
  * to request the value for 2-nd node (1 based) for the owner field the input should be
  * input=skaleConfig.sChain.nodes.1.owner (inside skaled node indexes are 0 based)
  * so one should pass the following as calldata
- * toBytes( ( ( input.length + 1 ) / 32 ) * 32) + toBytes(input)
- *
+ * toBytes( input.length + toBytes(input) )
  */
 ETH_REGISTER_PRECOMPILED( getConfigVariableAddress )( bytesConstRef _in ) {
     try {
diff --git a/test/unittests/libethereum/PrecompiledTest.cpp b/test/unittests/libethereum/PrecompiledTest.cpp
index f380d6745..4ede56bb3 100644
--- a/test/unittests/libethereum/PrecompiledTest.cpp
+++ b/test/unittests/libethereum/PrecompiledTest.cpp
@@ -1715,25 +1715,32 @@ BOOST_AUTO_TEST_CASE( getConfigVariableUint256 ) {
     dev::eth::g_skaleHost = testClient->skaleHost();
 
     PrecompiledExecutor exec = PrecompiledRegistrar::executor( "getConfigVariableUint256" );
+    std::string input = stringToHex( "skaleConfig.sChain.nodes.0.id" );
+    input = input.substr(0, 58); // remove 0s in the end
 
-    bytes in = fromHex( numberToHex( 32 ) + stringToHex( "skaleConfig.sChain.nodes.0.id" ) );
+    bytes in = fromHex( numberToHex( 29 ) + input );
     auto res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( res.first );
     BOOST_REQUIRE( dev::fromBigEndian<dev::u256>( res.second ) == 30 );
 
-    in = fromHex( numberToHex( 64 ) + stringToHex( "skaleConfig.sChain.nodes.0.schainIndex" ) );
+    input = stringToHex( "skaleConfig.sChain.nodes.0.schainIndex" );
+    input = input.substr(0, 76); // remove 0s in the end
+    in = fromHex( numberToHex( 38 ) + input );
     res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( res.first );
     BOOST_REQUIRE( dev::fromBigEndian<dev::u256>( res.second ) == 13 );
 
-    in = fromHex( numberToHex( 32 ) + stringToHex( "skaleConfig.sChain.nodes.0.owner" ) );
+    input = stringToHex( "skaleConfig.sChain.nodes.0.owner" );
+    in = fromHex( numberToHex( 32 ) + input );
     res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( !res.first );
 
-    in = fromHex( numberToHex( 64 ) + stringToHex( "skaleConfig.sChain.nodes.0.unknownField" ) );
+    input = stringToHex( "skaleConfig.sChain.nodes.0.unknownField" );
+    input = input.substr(0, 78); // remove 0s in the end
+    in = fromHex( numberToHex( 39 ) + input );
     res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( !res.first );
@@ -1767,23 +1774,31 @@ BOOST_AUTO_TEST_CASE( getConfigVariableAddress ) {
 
     PrecompiledExecutor exec = PrecompiledRegistrar::executor( "getConfigVariableAddress" );
 
-    bytes in = fromHex( numberToHex( 32 ) + stringToHex( "skaleConfig.sChain.nodes.0.owner" ) );
+    std::string input = stringToHex( "skaleConfig.sChain.nodes.0.owner" );
+    bytes in = fromHex( numberToHex( 32 ) + input );
     auto res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( res.first );
     BOOST_REQUIRE( res.second == fromHex("0x23bbe8db4e347b4e8c937c1c8350e4b5ed33adb3db69cbdb7a38e1f40a1b82fe") );
 
-    in = fromHex( numberToHex( 32 ) + stringToHex( "skaleConfig.sChain.nodes.0.id" ) );
+    input = stringToHex( "skaleConfig.sChain.nodes.0.id" );
+    input = input.substr(0, 58); // remove 0s in the end
+
+    in = fromHex( numberToHex( 29 ) + input );
     res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( !res.first );
 
-    in = fromHex( numberToHex( 64 ) + stringToHex( "skaleConfig.sChain.nodes.0.schainIndex" ) );
+    input = stringToHex( "skaleConfig.sChain.nodes.0.schainIndex" );
+    input = input.substr(0, 76); // remove 0s in the end
+    in = fromHex( numberToHex( 38 ) + input );
     res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( !res.first );
 
-    in = fromHex( numberToHex( 64 ) + stringToHex( "skaleConfig.sChain.nodes.0.unknownField" ) );
+    input = stringToHex( "skaleConfig.sChain.nodes.0.unknownField" );
+    input = input.substr(0, 78); // remove 0s in the end
+    in = fromHex( numberToHex( 39 ) + input );
     res = exec( bytesConstRef( in.data(), in.size() ) );
 
     BOOST_REQUIRE( !res.first );