- ACSE: fixed out-of-bounds read in parseAarqPdu function (LIB61850-441)(#512)

src/mms/iso_acse/acse.c

@@ -263,13 +263,17 @@ parseAarqPdu(AcseConnection* self, uint8_t* buffer, int bufPos, int maxBufPos)
     int authMechLen = 0;
     bool userInfoValid = false;
 
-    while (bufPos < maxBufPos) {
+    while (bufPos < maxBufPos)
+    {
         uint8_t tag = buffer[bufPos++];
         int len;
 
         bufPos = BerDecoder_decodeLength(buffer, &len, bufPos, maxBufPos);
 
-        if (bufPos < 0) {
+        if (len == 0)
+            continue;
+
+        if ((bufPos < 0) || (bufPos + len > maxBufPos)) {
             if (DEBUG_ACSE)
                 printf("ACSE: Invalid PDU!\n");
             return ACSE_ASSOCIATE_FAILED;