diff --git a/src/primitives/pak.cpp b/src/primitives/pak.cpp
index 42461b6aef..430e26ccc1 100644
--- a/src/primitives/pak.cpp
+++ b/src/primitives/pak.cpp
@@ -185,7 +185,7 @@ bool ScriptHasValidPAKProof(const CScript& script, const uint256& genesis_hash)
     std::vector<unsigned char> extracted_pubkey_hash;
 
     // Get full pubkey
-    if (!script.GetOp(pc, opcode, data) || opcode != 33 || data.size() != 33) {
+    if (!script.GetOp(pc, opcode, data) || data.size() != 33 || opcode > OP_PUSHDATA4) {
         return false;
     }
     CPubKey full_pubkey(data.begin(), data.end());
diff --git a/src/script/script.cpp b/src/script/script.cpp
index b277b8f2a4..386f9a19a5 100644
--- a/src/script/script.cpp
+++ b/src/script/script.cpp
@@ -213,17 +213,24 @@ bool CScript::IsPegoutScript(uint256& genesis_hash, CScript& pegout_scriptpubkey
         return false;
     }
 
-    if (!GetOp(pc, opcode, data) || data.size() != 32 ) {
+    if (!GetOp(pc, opcode, data) || data.size() != 32 || opcode > OP_PUSHDATA4) {
         return false;
     }
     genesis_hash = uint256(data);
 
     // Read in parent chain destination scriptpubkey
-    if (!GetOp(pc, opcode, data) || data.size() == 0 ) {
+    if (!GetOp(pc, opcode, data) || opcode > OP_PUSHDATA4 ) {
         return false;
     }
     pegout_scriptpubkey = CScript(data.begin(), data.end());
 
+    // All extra opcodes must be pushes
+    while(GetOp(pc, opcode, data)) {
+        if (opcode > OP_PUSHDATA4) {
+            return false;
+        }
+    }
+
     return true;
 }