diff --git a/codec/decoder/core/inc/error_code.h b/codec/decoder/core/inc/error_code.h
index d43ac30c..ebf46f7e 100644
--- a/codec/decoder/core/inc/error_code.h
+++ b/codec/decoder/core/inc/error_code.h
@@ -133,6 +133,7 @@ enum {
   ERR_INFO_INVALID_CBP,
   ERR_INFO_DQUANT_OUT_OF_RANGE,
   ERR_INFO_CAVLC_INVALID_PREFIX,
+  ERR_INFO_CAVLC_INVALID_LEVEL,
   ERR_INFO_CAVLC_INVALID_TOTAL_COEFF_OR_TRAILING_ONES,
   ERR_INFO_CAVLC_INVALID_ZERO_LEFT,
   ERR_INFO_CAVLC_INVALID_RUN_BEFORE,
diff --git a/codec/decoder/core/src/parse_mb_syn_cavlc.cpp b/codec/decoder/core/src/parse_mb_syn_cavlc.cpp
index 35d4f47c..80782ad4 100644
--- a/codec/decoder/core/src/parse_mb_syn_cavlc.cpp
+++ b/codec/decoder/core/src/parse_mb_syn_cavlc.cpp
@@ -718,8 +718,10 @@ int32_t WelsResidualBlockCavlc (SVlcTable* pVlcTable, uint8_t* pNonZeroCountCach
   if ((uiTrailingOnes > 3) || (uiTotalCoeff > 16)) { /////////////////check uiTrailingOnes and uiTotalCoeff
     return ERR_INFO_CAVLC_INVALID_TOTAL_COEFF_OR_TRAILING_ONES;
   }
-  iUsedBits += CavlcGetLevelVal (iLevel, &sReadBitsCache, uiTotalCoeff, uiTrailingOnes);
-
+  if ((i = CavlcGetLevelVal (iLevel, &sReadBitsCache, uiTotalCoeff, uiTrailingOnes)) == -1) {
+    return ERR_INFO_CAVLC_INVALID_LEVEL;
+  }
+  iUsedBits += i;
   if (uiTotalCoeff < iMaxNumCoeff) {
     iUsedBits += CavlcGetTotalZeros (iZerosLeft, &sReadBitsCache, uiTotalCoeff, pVlcTable, bChromaDc);
   } else {