diff --git a/src/lib/waku_message/version_1.ts b/src/lib/waku_message/version_1.ts
index 6ba8f0f388..f497e4bcbe 100644
--- a/src/lib/waku_message/version_1.ts
+++ b/src/lib/waku_message/version_1.ts
@@ -98,7 +98,7 @@ export function clearDecode(
   start += sizeOfPayloadSizeField;
   const payload = buf.slice(start, start + payloadSize);
 
-  const isSigned = (buf.readUIntLE(0, 1) & IsSignedMask) == IsSignedMask;
+  const isSigned = isMessageSigned(buf);
   if (isSigned) {
     const signature = getSignature(buf);
     const hash = getHash(buf, isSigned);
@@ -131,6 +131,10 @@ function getPayloadSize(
   return payloadSizeDataView.getInt32(0, true);
 }
 
+function isMessageSigned(message: Buffer): boolean {
+  return (message.readUIntLE(0, 1) & IsSignedMask) == IsSignedMask;
+}
+
 /**
  * Proceed with Asymmetric encryption of the data as per [26/WAKU-PAYLOAD](https://rfc.vac.dev/spec/26/).
  * The data MUST be flags | payload-length | payload | [signature].