diff --git a/data_model/src/block.rs b/data_model/src/block.rs
index 1cbfeb543e0..705aff16b93 100644
--- a/data_model/src/block.rs
+++ b/data_model/src/block.rs
@@ -318,15 +318,9 @@ impl BlockSignature {
 }
 
 mod candidate {
-    #[cfg(not(feature = "std"))]
-    use alloc::collections::BTreeSet;
-    #[cfg(feature = "std")]
-    use std::collections::BTreeSet;
-
     use parity_scale_codec::Input;
 
     use super::*;
-    use crate::isi::InstructionBox;
 
     #[derive(Decode, Deserialize)]
     struct SignedBlockCandidate {
@@ -336,10 +330,13 @@ mod candidate {
 
     impl SignedBlockCandidate {
         fn validate(self) -> Result<SignedBlockV1, &'static str> {
-            self.validate_signatures()?;
-            self.validate_header()?;
-            if self.payload.header.height.get() == 1 {
-                self.validate_genesis()?;
+            #[cfg(not(target_family = "wasm"))]
+            {
+                self.validate_signatures()?;
+                self.validate_header()?;
+                if self.payload.header.height.get() == 1 {
+                    self.validate_genesis()?;
+                }
             }
 
             Ok(SignedBlockV1 {
@@ -348,7 +345,10 @@ mod candidate {
             })
         }
 
+        #[cfg(not(target_family = "wasm"))]
         fn validate_genesis(&self) -> Result<(), &'static str> {
+            use crate::isi::InstructionBox;
+
             let transactions = self.payload.transactions.as_slice();
             for transaction in transactions {
                 if transaction.error.is_some() {
@@ -382,7 +382,13 @@ mod candidate {
             Ok(())
         }
 
+        #[cfg(not(target_family = "wasm"))]
         fn validate_signatures(&self) -> Result<(), &'static str> {
+            #[cfg(not(feature = "std"))]
+            use alloc::collections::BTreeSet;
+            #[cfg(feature = "std")]
+            use std::collections::BTreeSet;
+
             if self.signatures.is_empty() && self.payload.header.height.get() != 1 {
                 return Err("Block missing signatures");
             }
@@ -401,6 +407,7 @@ mod candidate {
             Ok(())
         }
 
+        #[cfg(not(target_family = "wasm"))]
         fn validate_header(&self) -> Result<(), &'static str> {
             let actual_txs_hash = self.payload.header.transactions_hash;
 
diff --git a/data_model/src/lib.rs b/data_model/src/lib.rs
index 7a52f92d86e..1c6c659d910 100644
--- a/data_model/src/lib.rs
+++ b/data_model/src/lib.rs
@@ -1,5 +1,14 @@
 //! Iroha Data Model contains structures for Domains, Peers, Accounts and Assets with simple,
 //! non-specific functions like serialization.
+//!
+//! ## Note about WASM and deserialization
+//! Some structs performs validation during deserialization.
+//! (e.g. [`transaction::candidate::SignedTransactionCandidate`]).
+//! However such validation was disabled when compiled to WASM,
+//! Validation at WASM side is not necessary,
+//! because validation was already performed on host side,
+//! and host is a trusted entity.
+//! This gives about 50% performance boost, see #4995.
 
 // Clippy bug
 #![allow(clippy::items_after_test_module)]
diff --git a/data_model/src/name.rs b/data_model/src/name.rs
index bf87b77a275..a0b46cd8a97 100644
--- a/data_model/src/name.rs
+++ b/data_model/src/name.rs
@@ -105,9 +105,11 @@ impl<'de> Deserialize<'de> for Name {
     where
         D: serde::Deserializer<'de>,
     {
+        #[cfg(not(target_family = "wasm"))]
         use serde::de::Error as _;
 
         let candidate = ConstString::deserialize(deserializer)?;
+        #[cfg(not(target_family = "wasm"))]
         Self::validate_str(&candidate).map_err(D::Error::custom)?;
 
         Ok(Self(candidate))
@@ -116,9 +118,9 @@ impl<'de> Deserialize<'de> for Name {
 impl Decode for Name {
     fn decode<I: Input>(input: &mut I) -> Result<Self, parity_scale_codec::Error> {
         let name = ConstString::decode(input)?;
-        Self::validate_str(&name)
-            .map(|()| Self(name))
-            .map_err(|error| error.reason.into())
+        #[cfg(not(target_family = "wasm"))]
+        Self::validate_str(&name).map_err(|error| parity_scale_codec::Error::from(error.reason))?;
+        Ok(Self(name))
     }
 }
 
diff --git a/data_model/src/query/mod.rs b/data_model/src/query/mod.rs
index d79b9a60c5a..32878184256 100644
--- a/data_model/src/query/mod.rs
+++ b/data_model/src/query/mod.rs
@@ -375,11 +375,13 @@ mod candidate {
 
     impl SignedQueryCandidate {
         fn validate(self) -> Result<SignedQueryV1, &'static str> {
-            let QuerySignature(signature) = &self.signature;
-
-            signature
-                .verify(&self.payload.authority.signatory, &self.payload)
-                .map_err(|_| "Query request signature is not valid")?;
+            #[cfg(not(target_family = "wasm"))]
+            {
+                let QuerySignature(signature) = &self.signature;
+                signature
+                    .verify(&self.payload.authority.signatory, &self.payload)
+                    .map_err(|_| "Query request signature is not valid")?;
+            }
 
             Ok(SignedQueryV1 {
                 payload: self.payload,
diff --git a/data_model/src/transaction.rs b/data_model/src/transaction.rs
index ef57fe45b11..e1efd11e902 100644
--- a/data_model/src/transaction.rs
+++ b/data_model/src/transaction.rs
@@ -335,7 +335,9 @@ mod candidate {
 
     impl SignedTransactionCandidate {
         fn validate(self) -> Result<SignedTransactionV1, &'static str> {
+            #[cfg(not(target_family = "wasm"))]
             self.validate_instructions()?;
+            #[cfg(not(target_family = "wasm"))]
             self.validate_signature()?;
 
             Ok(SignedTransactionV1 {
@@ -344,6 +346,7 @@ mod candidate {
             })
         }
 
+        #[cfg(not(target_family = "wasm"))]
         fn validate_instructions(&self) -> Result<(), &'static str> {
             if let Executable::Instructions(instructions) = &self.payload.instructions {
                 if instructions.is_empty() {
@@ -354,6 +357,7 @@ mod candidate {
             Ok(())
         }
 
+        #[cfg(not(target_family = "wasm"))]
         fn validate_signature(&self) -> Result<(), &'static str> {
             let TransactionSignature(signature) = &self.signature;
 
diff --git a/defaults/executor.wasm b/defaults/executor.wasm
index 6933f17e8ad..89ec026fae2 100644
Binary files a/defaults/executor.wasm and b/defaults/executor.wasm differ