diff --git a/OpenCL/m05500_a3-optimized.cl b/OpenCL/m05500_a3-optimized.cl
index a2e4a220f..5fb88b555 100644
--- a/OpenCL/m05500_a3-optimized.cl
+++ b/OpenCL/m05500_a3-optimized.cl
@@ -969,6 +969,76 @@ __kernel void m05500_m08 (KERN_ATTR_VECTOR ())
 
 __kernel void m05500_m16 (KERN_ATTR_VECTOR ())
 {
+  /**
+   * modifier
+   */
+
+  const u64 gid = get_global_id (0);
+  const u64 lid = get_local_id (0);
+  const u64 lsz = get_local_size (0);
+
+  /**
+   * sbox, kbox
+   */
+
+  __local u32 s_SPtrans[8][64];
+  __local u32 s_skb[8][64];
+
+  for (u32 i = lid; i < 64; i += lsz)
+  {
+    s_SPtrans[0][i] = c_SPtrans[0][i];
+    s_SPtrans[1][i] = c_SPtrans[1][i];
+    s_SPtrans[2][i] = c_SPtrans[2][i];
+    s_SPtrans[3][i] = c_SPtrans[3][i];
+    s_SPtrans[4][i] = c_SPtrans[4][i];
+    s_SPtrans[5][i] = c_SPtrans[5][i];
+    s_SPtrans[6][i] = c_SPtrans[6][i];
+    s_SPtrans[7][i] = c_SPtrans[7][i];
+
+    s_skb[0][i] = c_skb[0][i];
+    s_skb[1][i] = c_skb[1][i];
+    s_skb[2][i] = c_skb[2][i];
+    s_skb[3][i] = c_skb[3][i];
+    s_skb[4][i] = c_skb[4][i];
+    s_skb[5][i] = c_skb[5][i];
+    s_skb[6][i] = c_skb[6][i];
+    s_skb[7][i] = c_skb[7][i];
+  }
+
+  barrier (CLK_LOCAL_MEM_FENCE);
+
+  if (gid >= gid_max) return;
+
+  /**
+   * base
+   */
+
+  u32 w[16];
+
+  w[ 0] = pws[gid].i[ 0];
+  w[ 1] = pws[gid].i[ 1];
+  w[ 2] = pws[gid].i[ 2];
+  w[ 3] = pws[gid].i[ 3];
+  w[ 4] = pws[gid].i[ 4];
+  w[ 5] = pws[gid].i[ 5];
+  w[ 6] = pws[gid].i[ 6];
+  w[ 7] = pws[gid].i[ 7];
+  w[ 8] = pws[gid].i[ 8];
+  w[ 9] = pws[gid].i[ 9];
+  w[10] = pws[gid].i[10];
+  w[11] = pws[gid].i[11];
+  w[12] = pws[gid].i[12];
+  w[13] = pws[gid].i[13];
+  w[14] = pws[gid].i[14];
+  w[15] = 0;
+
+  const u32 pw_len = pws[gid].pw_len & 63;
+
+  /**
+   * main
+   */
+
+  m05500m (s_SPtrans, s_skb, w, pw_len, pws, rules_buf, combs_buf, words_buf_r, tmps, hooks, bitmaps_buf_s1_a, bitmaps_buf_s1_b, bitmaps_buf_s1_c, bitmaps_buf_s1_d, bitmaps_buf_s2_a, bitmaps_buf_s2_b, bitmaps_buf_s2_c, bitmaps_buf_s2_d, plains_buf, digests_buf, hashes_shown, salt_bufs, esalt_bufs, d_return_buf, d_extra0_buf, d_extra1_buf, d_extra2_buf, d_extra3_buf, bitmap_mask, bitmap_shift1, bitmap_shift2, salt_pos, loop_pos, loop_cnt, il_cnt, digests_cnt, digests_offset, combs_mode, gid_max);
 }
 
 __kernel void m05500_s04 (KERN_ATTR_VECTOR ())
@@ -1121,4 +1191,74 @@ __kernel void m05500_s08 (KERN_ATTR_VECTOR ())
 
 __kernel void m05500_s16 (KERN_ATTR_VECTOR ())
 {
+  /**
+   * modifier
+   */
+
+  const u64 gid = get_global_id (0);
+  const u64 lid = get_local_id (0);
+  const u64 lsz = get_local_size (0);
+
+  /**
+   * sbox, kbox
+   */
+
+  __local u32 s_SPtrans[8][64];
+  __local u32 s_skb[8][64];
+
+  for (u32 i = lid; i < 64; i += lsz)
+  {
+    s_SPtrans[0][i] = c_SPtrans[0][i];
+    s_SPtrans[1][i] = c_SPtrans[1][i];
+    s_SPtrans[2][i] = c_SPtrans[2][i];
+    s_SPtrans[3][i] = c_SPtrans[3][i];
+    s_SPtrans[4][i] = c_SPtrans[4][i];
+    s_SPtrans[5][i] = c_SPtrans[5][i];
+    s_SPtrans[6][i] = c_SPtrans[6][i];
+    s_SPtrans[7][i] = c_SPtrans[7][i];
+
+    s_skb[0][i] = c_skb[0][i];
+    s_skb[1][i] = c_skb[1][i];
+    s_skb[2][i] = c_skb[2][i];
+    s_skb[3][i] = c_skb[3][i];
+    s_skb[4][i] = c_skb[4][i];
+    s_skb[5][i] = c_skb[5][i];
+    s_skb[6][i] = c_skb[6][i];
+    s_skb[7][i] = c_skb[7][i];
+  }
+
+  barrier (CLK_LOCAL_MEM_FENCE);
+
+  if (gid >= gid_max) return;
+
+  /**
+   * base
+   */
+
+  u32 w[16];
+
+  w[ 0] = pws[gid].i[ 0];
+  w[ 1] = pws[gid].i[ 1];
+  w[ 2] = pws[gid].i[ 2];
+  w[ 3] = pws[gid].i[ 3];
+  w[ 4] = pws[gid].i[ 4];
+  w[ 5] = pws[gid].i[ 5];
+  w[ 6] = pws[gid].i[ 6];
+  w[ 7] = pws[gid].i[ 7];
+  w[ 8] = pws[gid].i[ 8];
+  w[ 9] = pws[gid].i[ 9];
+  w[10] = pws[gid].i[10];
+  w[11] = pws[gid].i[11];
+  w[12] = pws[gid].i[12];
+  w[13] = pws[gid].i[13];
+  w[14] = pws[gid].i[14];
+  w[15] = 0;
+
+  const u32 pw_len = pws[gid].pw_len & 63;
+
+  /**
+   * main
+   */
+
+  m05500s (s_SPtrans, s_skb, w, pw_len, pws, rules_buf, combs_buf, words_buf_r, tmps, hooks, bitmaps_buf_s1_a, bitmaps_buf_s1_b, bitmaps_buf_s1_c, bitmaps_buf_s1_d, bitmaps_buf_s2_a, bitmaps_buf_s2_b, bitmaps_buf_s2_c, bitmaps_buf_s2_d, plains_buf, digests_buf, hashes_shown, salt_bufs, esalt_bufs, d_return_buf, d_extra0_buf, d_extra1_buf, d_extra2_buf, d_extra3_buf, bitmap_mask, bitmap_shift1, bitmap_shift2, salt_pos, loop_pos, loop_cnt, il_cnt, digests_cnt, digests_offset, combs_mode, gid_max);
 }
diff --git a/docs/changes.txt b/docs/changes.txt
index 926763148..a6d9428ba 100644
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -22,6 +22,7 @@
 - Fixed output of IKE PSK (mode 5300 and 5400) hashes to have separators at right position
 - Fixed the validation of the --brain-client-features command line argument (only values 1, 2 or 3 are allowed)
 - Fixed cracking of Cisco-PIX and Cisco-ASA MD5 passwords in mask-attack mode if mask > length 16
+- Fixed cracking of NetNTLMv1 passwords in mask-attack mode if mask > length 16 (optimized kernels only)
 - Fixed the 7-Zip parser to allow the entire supported range of encrypted and decrypted data lengths
 - Fixed incorrect progress-only result in a special race condition
 - Fixed maximum password length limit which was announced as 256 but actually was 255