diff --git a/core/vm/contracts.go b/core/vm/contracts.go
index 4a71342e9e..2443aaae8e 100644
--- a/core/vm/contracts.go
+++ b/core/vm/contracts.go
@@ -500,12 +500,13 @@ func (c *bigModExp) RequiredGas(input []byte) uint64 {
 
 func (c *bigModExp) Run(input []byte) ([]byte, error) {
 	var (
-		baseLenBig = new(big.Int).SetBytes(getData(input, 0, 32))
-		expLenBig  = new(big.Int).SetBytes(getData(input, 32, 32))
-		modLenBig  = new(big.Int).SetBytes(getData(input, 64, 32))
-		baseLen    = baseLenBig.Uint64()
-		expLen     = expLenBig.Uint64()
-		modLen     = modLenBig.Uint64()
+		baseLenBig       = new(big.Int).SetBytes(getData(input, 0, 32))
+		expLenBig        = new(big.Int).SetBytes(getData(input, 32, 32))
+		modLenBig        = new(big.Int).SetBytes(getData(input, 64, 32))
+		baseLen          = baseLenBig.Uint64()
+		expLen           = expLenBig.Uint64()
+		modLen           = modLenBig.Uint64()
+		inputLenOverflow = max(baseLenBig.BitLen(), expLenBig.BitLen(), modLenBig.BitLen()) > 64
 	)
 	if len(input) > 96 {
 		input = input[96:]
@@ -513,12 +514,8 @@ func (c *bigModExp) Run(input []byte) ([]byte, error) {
 		input = input[:0]
 	}
 
-	inputLensHighBitsSet := baseLenBig.Rsh(baseLenBig, 64).Cmp(common.Big0) != 0 ||
-		expLenBig.Rsh(expLenBig, 64).Cmp(common.Big0) != 0 ||
-		modLenBig.Rsh(modLenBig, 64).Cmp(common.Big0) != 0
-
 	// enforce size cap for inputs
-	if c.eip7823 && (max(baseLen, expLen, modLen) > 1024 || inputLensHighBitsSet) {
+	if c.eip7823 && (inputLenOverflow || max(baseLen, expLen, modLen) > 1024) {
 		return nil, errors.New("one or more of base/exponent/modulus length exceeded 1024 bytes")
 	}
 	// Handle a special case when both the base and mod length is zero