diff --git a/webrtc/common_video/h264/h264_bitstream_parser.cc b/webrtc/common_video/h264/h264_bitstream_parser.cc
index 048cdd2f6e..4ad0ed4b28 100644
--- a/webrtc/common_video/h264/h264_bitstream_parser.cc
+++ b/webrtc/common_video/h264/h264_bitstream_parser.cc
@@ -19,6 +19,12 @@
 #include "webrtc/common_video/h264/h264_common.h"
 #include "webrtc/base/logging.h"
 
+namespace {
+const int kMaxAbsQpDeltaValue = 51;
+const int kMinQpValue = 0;
+const int kMaxQpValue = 51;
+}
+
 namespace webrtc {
 
 #define RETURN_ON_FAIL(x, res)        \
@@ -251,6 +257,12 @@ H264BitstreamParser::Result H264BitstreamParser::ParseNonParameterSetNalu(
   int32_t last_slice_qp_delta;
   RETURN_INV_ON_FAIL(
       slice_reader.ReadSignedExponentialGolomb(&last_slice_qp_delta));
+  if (abs(last_slice_qp_delta) > kMaxAbsQpDeltaValue) {
+    // Something has gone wrong, and the parsed value is invalid.
+    LOG(LS_WARNING) << "Parsed QP value out of range.";
+    return kInvalidStream;
+  }
+
   last_slice_qp_delta_ = rtc::Optional<int32_t>(last_slice_qp_delta);
   return kOk;
 }
@@ -291,7 +303,12 @@ void H264BitstreamParser::ParseBitstream(const uint8_t* bitstream,
 bool H264BitstreamParser::GetLastSliceQp(int* qp) const {
   if (!last_slice_qp_delta_ || !pps_)
     return false;
-  *qp = 26 + pps_->pic_init_qp_minus26 + *last_slice_qp_delta_;
+  const int parsed_qp = 26 + pps_->pic_init_qp_minus26 + *last_slice_qp_delta_;
+  if (parsed_qp < kMinQpValue || parsed_qp > kMaxQpValue) {
+    LOG(LS_ERROR) << "Parsed invalid QP from bitstream.";
+    return false;
+  }
+  *qp = parsed_qp;
   return true;
 }
 
diff --git a/webrtc/common_video/h264/pps_parser.cc b/webrtc/common_video/h264/pps_parser.cc
index 0215549959..b2860c221f 100644
--- a/webrtc/common_video/h264/pps_parser.cc
+++ b/webrtc/common_video/h264/pps_parser.cc
@@ -22,6 +22,11 @@
     return rtc::Optional<PpsParser::PpsState>(); \
   }
 
+namespace {
+const int kMaxPicInitQpDeltaValue = 25;
+const int kMinPicInitQpDeltaValue = -26;
+}
+
 namespace webrtc {
 
 // General note: this is based off the 02/2014 version of the H.264 standard.
@@ -162,6 +167,11 @@ rtc::Optional<PpsParser::PpsState> PpsParser::ParseInternal(
   // pic_init_qp_minus26: se(v)
   RETURN_EMPTY_ON_FAIL(
       bit_buffer->ReadSignedExponentialGolomb(&pps.pic_init_qp_minus26));
+  // Sanity-check parsed value
+  if (pps.pic_init_qp_minus26 > kMaxPicInitQpDeltaValue ||
+      pps.pic_init_qp_minus26 < kMinPicInitQpDeltaValue) {
+    RETURN_EMPTY_ON_FAIL(false);
+  }
   // pic_init_qs_minus26: se(v)
   RETURN_EMPTY_ON_FAIL(bit_buffer->ReadExponentialGolomb(&golomb_ignored));
   // chroma_qp_index_offset: se(v)
diff --git a/webrtc/common_video/h264/pps_parser_unittest.cc b/webrtc/common_video/h264/pps_parser_unittest.cc
index b9ec92ba25..03490647c0 100644
--- a/webrtc/common_video/h264/pps_parser_unittest.cc
+++ b/webrtc/common_video/h264/pps_parser_unittest.cc
@@ -201,7 +201,7 @@ TEST_F(PpsParserTest, ZeroPps) {
 
 TEST_F(PpsParserTest, MaxPps) {
   generated_pps_.bottom_field_pic_order_in_frame_present_flag = true;
-  generated_pps_.pic_init_qp_minus26 = std::numeric_limits<int32_t>::max();
+  generated_pps_.pic_init_qp_minus26 = 25;
   generated_pps_.redundant_pic_cnt_present_flag = 1;  // 1 bit value.
   generated_pps_.weighted_bipred_idc = (1 << 2) - 1;  // 2 bit value.
   generated_pps_.weighted_pred_flag = true;
@@ -210,7 +210,7 @@ TEST_F(PpsParserTest, MaxPps) {
   generated_pps_.sps_id = 1;
   RunTest();
 
-  generated_pps_.pic_init_qp_minus26 = std::numeric_limits<int32_t>::min() + 1;
+  generated_pps_.pic_init_qp_minus26 = -25;
   RunTest();
 }