diff --git a/lib_com/options.h b/lib_com/options.h
index 95ee270e432ce6c89eab25f57dba7e8601d0de52..10f358572ab5cf78f475f81a6f690a56c6736054 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -200,8 +200,12 @@
 #define FIX_629_UBSAN_MD_MAX_BITS                       /*Dlb : Fix for UBSAN issue 629 for MD MAX bits calculation*/
 
 #define FIX_626_VARIABLE_TYPE_MDCT_CONC                 /* FhG: trivial fix to fix USAN error */
+
 #define FIX_616_DIV_ZERO_MCT                            /*FhG : Fix UBSAN division by zero error of issue 616*/
-#define FIX_279_CODE_COVERAGE                           /*Dlb : issue 279 , clean up unused function*/
+
+#define FIX617_UBSAN_DIVBYZERO_STEREOCNG                /* Eri: Issue 617: Decoder UBSAN: division by zero in stereo cng when inut is 16kHz and output is 32kHz */
+#define FIX_279_CODE_COVERAGE                           /* Dlb : issue 279 , clean up unused function */
+
 /* ################## End BE DEVELOPMENT switches ######################### */
 
 
diff --git a/lib_dec/cng_dec.c b/lib_dec/cng_dec.c
index 64403736c43fae6a323f248a586792506f0bac99..92bb950c3831e1372e5485f9ae8487769c5526fe 100644
--- a/lib_dec/cng_dec.c
+++ b/lib_dec/cng_dec.c
@@ -737,9 +737,15 @@ static void shb_CNG_decod(
         ener = hTdCngDec->shb_cng_ener;
     }
 
+
     gain = (float) sqrt( pow( 10, 0.1f * ener ) * L_FRAME16k / ener_excSHB );
 
     st->hTdCngDec->shb_cng_gain = ener;
+#ifdef FIX617_UBSAN_DIVBYZERO_STEREOCNG
+#ifdef DEBUGGING
+    /* note: state shb_cng_gain is actually an energy value in dB */
+#endif
+#endif
 
     for ( i = 0; i < L_FRAME16k; i++ )
     {
@@ -783,6 +789,15 @@ void td_cng_dec_init(
     mvr2r( st->lsp_old, st->lspCNG, M );
     hTdCngDec->last_allow_cn_step = 0;
     hTdCngDec->shb_cng_ener = -6.02f;
+#ifdef FIX617_UBSAN_DIVBYZERO_STEREOCNG
+    if ( st->element_mode != EVS_MONO )
+    {
+        set_f( hTdCngDec->shb_lpcCNG, 0.0f, LPC_SHB_ORDER + 1 );
+        hTdCngDec->shb_lpcCNG[0] = 1.0f;
+        hTdCngDec->shb_cng_gain = -82.0; /* a  dB value approximately corresponding to  shb  index 0(used as index -15)   */
+    }
+#endif
+
     hTdCngDec->wb_cng_ener = -6.02f;
     hTdCngDec->last_wb_cng_ener = -6.02f;
     hTdCngDec->last_shb_cng_ener = -6.02f;
@@ -825,8 +840,10 @@ void td_cng_dec_init(
     hTdCngDec->shb_dtx_count = 0;
     hTdCngDec->trans_cnt = 0;
     hTdCngDec->burst_cnt = 0;
+
     hTdCngDec->last_shb_ener = 0.001f;
 
+
     set_f( hTdCngDec->interpol_3_2_cng_dec, 0.0f, INTERP_3_2_MEM_LEN );
 
     return;
diff --git a/lib_dec/ivas_stereo_cng_dec.c b/lib_dec/ivas_stereo_cng_dec.c
index c12498c015e6a9d54b79278ec89f36c8bacbf6c7..c674f8bec9115d8a517b44433c9e1cce4f43e750 100644
--- a/lib_dec/ivas_stereo_cng_dec.c
+++ b/lib_dec/ivas_stereo_cng_dec.c
@@ -342,12 +342,25 @@ static void stereo_dft_generate_comfort_noise(
         ptr0 = cngNoiseLevel_upd;
         ptr1 = ptr0 + 2;
         ptr2 = ptr1 + 1;
+#ifdef FIX617_UBSAN_DIVBYZERO_STEREOCNG
+        assert( st->lp_ener > 0.0f );
+        factor = 2.0f * sqrtf( st->lp_ener / st->L_frame * 0.5f ); /* fixed factor  in the loop below */
+        for ( i = 0; i < st->L_frame / 2 - 1; i++ )
+        {
+            ftmp = *ptr1 * *ptr1 + *ptr2 * *ptr2;
+            assert( ftmp > 0.0f );
+            *ptr0++ = factor * inv_sqrt( ftmp );
+            ptr1 += 2;
+            ptr2 += 2;
+        }
+#else
         for ( i = 0; i < st->L_frame / 2 - 1; i++ )
         {
             *ptr0++ = 2.0f * sqrtf( st->lp_ener / st->L_frame * 0.5f ) * inv_sqrt( *ptr1 * *ptr1 + *ptr2 * *ptr2 );
             ptr1 += 2;
             ptr2 += 2;
         }
+#endif
 
         if ( min( output_frame, L_FRAME32k ) - hFdCngCom->stopFFTbin > 0 )
         {
@@ -375,9 +388,22 @@ static void stereo_dft_generate_comfort_noise(
             ptr0 = shb_shape;
             ptr1 = ptr0 + 2;
             ptr2 = ptr1 + 1;
+
             for ( i = 0; i < L_FRAME16k / 2 - 1; i++ )
             {
+#ifdef FIX617_UBSAN_DIVBYZERO_STEREOCNG
+                ftmp = ( *ptr1 * *ptr1 + *ptr2 * *ptr2 );
+                assert( ftmp > 0.0f );
+                ftmp = 1.0f / ftmp;
+                /* in float:
+                     both a = "div"=(1/(x^2+y^2) and sqrt(a)  is used and summed up in the same loop.
+
+                  in BASOP:
+                    sum up  using inv_sqrt( *ptr1 * *ptr1 + *ptr2 * *ptr2 ), in this loop
+                    and then sum up  enr = sum( *ptr0 * *ptr0 ),  in a subsequent MAC loop  */
+#else
                 ftmp = 1.0f / ( *ptr1 * *ptr1 + *ptr2 * *ptr2 );
+#endif
                 enr += ftmp;
                 *ptr0++ = sqrtf( ftmp );
                 ptr1 += 2;
@@ -455,6 +481,9 @@ static void stereo_dft_generate_comfort_noise(
             {
 
                 /* high band generation, flipped spectrum */
+#ifdef FIX617_UBSAN_DIVBYZERO_STEREOCNG
+                assert( enr != 0.0f );
+#endif
                 scale = sqrtf( powf( 10, 0.1f * st->hTdCngDec->shb_cng_gain ) / enr );
                 ptr_shb = shb_shape + L_FRAME16k / 2 - 1;
                 /* Averaging for Nyquist frequency */