diff --git a/apps/createsamples/utility.cpp b/apps/createsamples/utility.cpp
index 5176f14836..c64995481c 100644
--- a/apps/createsamples/utility.cpp
+++ b/apps/createsamples/utility.cpp
@@ -1167,7 +1167,7 @@ void cvCreateTestSamples( const char* infoname,
             }
             else
             {
-                filename++;
+                filename++; // character after last / or \
             }
 
             count = MIN( count, cvbgdata->count );
@@ -1199,8 +1199,8 @@ void cvCreateTestSamples( const char* infoname,
                                          1, 0.0, 0.0, &data );
 
 
-                sprintf( filename, "%04d_%04d_%04d_%04d_%04d.jpg",
-                         (i + 1), x, y, width, height );
+                snprintf( filename, sizeof(fullname) - (filename - fullname), "%04d_%04d_%04d_%04d_%04d.jpg",
+                          (i + 1), x, y, width, height );
 
                 if( info )
                 {
diff --git a/modules/core/src/arithm.cpp b/modules/core/src/arithm.cpp
index fbc4959253..2a1ed7887a 100644
--- a/modules/core/src/arithm.cpp
+++ b/modules/core/src/arithm.cpp
@@ -489,7 +489,7 @@ static bool ocl_arithm_op(InputArray _src1, InputArray _src2, OutputArray _dst,
     int kercn = haveMask || haveScalar ? cn : ocl::predictOptimalVectorWidth(_src1, _src2, _dst);
     int scalarcn = kercn == 3 ? 4 : kercn, rowsPerWI = d.isIntel() ? 4 : 1;
 
-    char cvtstr[4][32], opts[1024];
+    char cvtstr[4][50], opts[1024];
     snprintf(opts, sizeof(opts), "-D %s%s -D %s -D srcT1=%s -D srcT1_C1=%s -D srcT2=%s -D srcT2_C1=%s "
             "-D dstT=%s -D DEPTH_dst=%d -D dstT_C1=%s -D workT=%s -D workST=%s -D scaleT=%s -D wdepth=%d -D convertToWT1=%s "
             "-D convertToWT2=%s -D convertToDT=%s%s -D cn=%d -D rowsPerWI=%d -D convertFromU=%s",
@@ -1098,7 +1098,7 @@ static bool ocl_compare(InputArray _src1, InputArray _src2, OutputArray _dst, in
 
     int scalarcn = kercn == 3 ? 4 : kercn;
     const char * const operationMap[] = { "==", ">", ">=", "<", "<=", "!=" };
-    char cvt[40];
+    char cvt[50];
 
     String opts = format("-D %s -D srcT1=%s -D dstT=%s -D DEPTH_dst=%d -D workT=srcT1 -D cn=%d"
                          " -D convertToDT=%s -D OP_CMP -D CMP_OPERATOR=%s -D srcT1_C1=%s"
diff --git a/modules/core/src/matmul.dispatch.cpp b/modules/core/src/matmul.dispatch.cpp
index 52200f097c..5a38f64eb8 100644
--- a/modules/core/src/matmul.dispatch.cpp
+++ b/modules/core/src/matmul.dispatch.cpp
@@ -1041,7 +1041,7 @@ static bool ocl_dot( InputArray _src1, InputArray _src2, double & res )
         wgs2_aligned <<= 1;
     wgs2_aligned >>= 1;
 
-    char cvt[40];
+    char cvt[50];
     ocl::Kernel k("reduce", ocl::core::reduce_oclsrc,
                   format("-D srcT=%s -D srcT1=%s -D dstT=%s -D dstTK=%s -D ddepth=%d -D convertToDT=%s -D OP_DOT "
                          "-D WGS=%d -D WGS2_ALIGNED=%d%s%s%s -D kercn=%d",
diff --git a/modules/core/src/matrix_operations.cpp b/modules/core/src/matrix_operations.cpp
index f9a50cd0ee..f5cafbd279 100644
--- a/modules/core/src/matrix_operations.cpp
+++ b/modules/core/src/matrix_operations.cpp
@@ -633,7 +633,7 @@ static bool ocl_reduce(InputArray _src, OutputArray _dst,
             static const size_t maxItemInGroupCount = 16;
             tileHeight = min(tileHeight, defDev.localMemSize() / buf_cols / CV_ELEM_SIZE(CV_MAKETYPE(wdepth, cn)) / maxItemInGroupCount);
         }
-        char cvt[3][40];
+        char cvt[3][50];
         cv::String build_opt = format("-D OP_REDUCE_PRE -D BUF_COLS=%d -D TILE_HEIGHT=%zu -D %s -D dim=1"
                                             " -D cn=%d -D ddepth=%d"
                                             " -D srcT=%s -D bufT=%s -D dstT=%s"
@@ -667,7 +667,7 @@ static bool ocl_reduce(InputArray _src, OutputArray _dst,
     }
     else
     {
-        char cvt[2][40];
+        char cvt[2][50];
         cv::String build_opt = format("-D %s -D dim=%d -D cn=%d -D ddepth=%d"
                                       " -D srcT=%s -D dstT=%s -D dstT0=%s -D convertToWT=%s"
                                       " -D convertToDT=%s -D convertToDT0=%s%s",
diff --git a/modules/core/src/mean.dispatch.cpp b/modules/core/src/mean.dispatch.cpp
index 7a8f9413fc..62198d38bf 100644
--- a/modules/core/src/mean.dispatch.cpp
+++ b/modules/core/src/mean.dispatch.cpp
@@ -227,7 +227,7 @@ static bool ocl_meanStdDev( InputArray _src, OutputArray _mean, OutputArray _sdv
         if ( (!doubleSupport && depth == CV_64F) )
             return false;
 
-        char cvt[2][40];
+        char cvt[2][50];
         String opts = format("-D srcT=%s -D srcT1=%s -D dstT=%s -D dstT1=%s -D sqddepth=%d"
                              " -D sqdstT=%s -D sqdstT1=%s -D convertToSDT=%s -D cn=%d%s%s"
                              " -D convertToDT=%s -D WGS=%d -D WGS2_ALIGNED=%d%s%s",
diff --git a/modules/core/src/minmax.cpp b/modules/core/src/minmax.cpp
index f738a87e4f..e03f939d07 100644
--- a/modules/core/src/minmax.cpp
+++ b/modules/core/src/minmax.cpp
@@ -1029,7 +1029,7 @@ bool ocl_minMaxIdx( InputArray _src, double* minVal, double* maxVal, int* minLoc
             needMaxLoc = true;
     }
 
-    char cvt[2][40];
+    char cvt[2][50];
     String opts = format("-D DEPTH_%d -D srcT1=%s%s -D WGS=%d -D srcT=%s"
                          " -D WGS2_ALIGNED=%d%s%s%s -D kercn=%d%s%s%s%s"
                          " -D dstT1=%s -D dstT=%s -D convertToDT=%s%s%s%s%s -D wdepth=%d -D convertFromU=%s"
diff --git a/modules/core/src/norm.cpp b/modules/core/src/norm.cpp
index 4df25f4957..dc22b73722 100644
--- a/modules/core/src/norm.cpp
+++ b/modules/core/src/norm.cpp
@@ -1319,7 +1319,7 @@ static bool ocl_normalize( InputArray _src, InputOutputArray _dst, InputArray _m
         if ((sdepth == CV_64F || ddepth == CV_64F) && !doubleSupport)
             return false;
 
-        char cvt[2][40];
+        char cvt[2][50];
         String opts = format("-D srcT=%s -D dstT=%s -D convertToWT=%s -D cn=%d -D rowsPerWI=%d"
                              " -D convertToDT=%s -D workT=%s%s%s%s -D srcT1=%s -D dstT1=%s",
                              ocl::typeToStr(stype), ocl::typeToStr(dtype),
diff --git a/modules/core/src/ocl.cpp b/modules/core/src/ocl.cpp
index 51acc68879..e4d9f52da9 100644
--- a/modules/core/src/ocl.cpp
+++ b/modules/core/src/ocl.cpp
@@ -6983,7 +6983,7 @@ const char* typeToStr(int type)
     {
         "uchar", "uchar2", "uchar3", "uchar4", 0, 0, 0, "uchar8", 0, 0, 0, 0, 0, 0, 0, "uchar16",
         "char", "char2", "char3", "char4", 0, 0, 0, "char8", 0, 0, 0, 0, 0, 0, 0, "char16",
-        "ushort", "ushort2", "ushort3", "ushort4",0, 0, 0, "ushort8", 0, 0, 0, 0, 0, 0, 0, "ushort16",
+        "ushort", "ushort2", "ushort3", "ushort4", 0, 0, 0, "ushort8", 0, 0, 0, 0, 0, 0, 0, "ushort16",
         "short", "short2", "short3", "short4", 0, 0, 0, "short8", 0, 0, 0, 0, 0, 0, 0, "short16",
         "int", "int2", "int3", "int4", 0, 0, 0, "int8", 0, 0, 0, 0, 0, 0, 0, "int16",
         "float", "float2", "float3", "float4", 0, 0, 0, "float8", 0, 0, 0, 0, 0, 0, 0, "float16",
@@ -6992,7 +6992,7 @@ const char* typeToStr(int type)
         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
     };
     int cn = CV_MAT_CN(type), depth = CV_MAT_DEPTH(type);
-    const char* result = cn > 16 ? 0 : tab[depth*16 + cn-1];
+    const char* result = cn > 16 ? nullptr : tab[depth*16 + cn-1];
     CV_Assert(result);
     return result;
 }
@@ -7003,7 +7003,7 @@ const char* memopTypeToStr(int type)
     {
         "uchar", "uchar2", "uchar3", "uchar4", 0, 0, 0, "uchar8", 0, 0, 0, 0, 0, 0, 0, "uchar16",
         "char", "char2", "char3", "char4", 0, 0, 0, "char8", 0, 0, 0, 0, 0, 0, 0, "char16",
-        "ushort", "ushort2", "ushort3", "ushort4",0, 0, 0, "ushort8", 0, 0, 0, 0, 0, 0, 0, "ushort16",
+        "ushort", "ushort2", "ushort3", "ushort4", 0, 0, 0, "ushort8", 0, 0, 0, 0, 0, 0, 0, "ushort16",
         "short", "short2", "short3", "short4", 0, 0, 0, "short8", 0, 0, 0, 0, 0, 0, 0, "short16",
         "int", "int2", "int3", "int4", 0, 0, 0, "int8", 0, 0, 0, 0, 0, 0, 0, "int16",
         "int", "int2", "int3", "int4", 0, 0, 0, "int8", 0, 0, 0, 0, 0, 0, 0, "int16",
@@ -7012,7 +7012,7 @@ const char* memopTypeToStr(int type)
         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
     };
     int cn = CV_MAT_CN(type), depth = CV_MAT_DEPTH(type);
-    const char* result = cn > 16 ? 0 : tab[depth*16 + cn-1];
+    const char* result = cn > 16 ? nullptr : tab[depth*16 + cn-1];
     CV_Assert(result);
     return result;
 }
@@ -7039,6 +7039,9 @@ const char* vecopTypeToStr(int type)
 
 const char* convertTypeStr(int sdepth, int ddepth, int cn, char* buf)
 {
+    // Since the size of buf is not given, we assume 50 because that's what all callers use.
+    constexpr size_t buf_max = 50;
+
     if( sdepth == ddepth )
         return "noconvert";
     const char *typestr = typeToStr(CV_MAKETYPE(ddepth, cn));
@@ -7047,12 +7050,12 @@ const char* convertTypeStr(int sdepth, int ddepth, int cn, char* buf)
         (ddepth == CV_16S && sdepth <= CV_8S) ||
         (ddepth == CV_16U && sdepth == CV_8U))
     {
-        sprintf(buf, "convert_%s", typestr);
+        snprintf(buf, buf_max, "convert_%s", typestr);
     }
     else if( sdepth >= CV_32F )
-        sprintf(buf, "convert_%s%s_rte", typestr, (ddepth < CV_32S ? "_sat" : ""));
+        snprintf(buf, buf_max, "convert_%s%s_rte", typestr, (ddepth < CV_32S ? "_sat" : ""));
     else
-        sprintf(buf, "convert_%s_sat", typestr);
+        snprintf(buf, buf_max, "convert_%s_sat", typestr);
 
     return buf;
 }
diff --git a/modules/core/src/persistence.cpp b/modules/core/src/persistence.cpp
index 59f843d5bc..0d64bab094 100644
--- a/modules/core/src/persistence.cpp
+++ b/modules/core/src/persistence.cpp
@@ -161,14 +161,21 @@ static int symbolToType(char c)
     return static_cast<int>(pos - symbols);
 }
 
-char* encodeFormat(int elem_type, char* dt)
+char* encodeFormat(int elem_type, char* dt, size_t dt_len)
 {
     int cn = (elem_type == CV_SEQ_ELTYPE_PTR/*CV_USRTYPE1*/) ? 1 : CV_MAT_CN(elem_type);
     char symbol = (elem_type == CV_SEQ_ELTYPE_PTR/*CV_USRTYPE1*/) ? 'r' : typeSymbol(CV_MAT_DEPTH(elem_type));
-    sprintf(dt, "%d%c", cn, symbol);
+    snprintf(dt, dt_len, "%d%c", cn, symbol);
     return dt + (cn == 1 ? 1 : 0);
 }
 
+// Deprecated due to size of dt buffer being unknowable.
+char* encodeFormat(int elem_type, char* dt)
+{
+    constexpr size_t max = 20+1+1; // UINT64_MAX + one char + nul termination.
+    return encodeFormat(elem_type, dt, max);
+}
+
 int decodeFormat( const char* dt, int* fmt_pairs, int max_len )
 {
     int fmt_pair_count = 0;
diff --git a/modules/core/src/persistence.hpp b/modules/core/src/persistence.hpp
index fb7f5acf45..4b579303fa 100644
--- a/modules/core/src/persistence.hpp
+++ b/modules/core/src/persistence.hpp
@@ -91,7 +91,8 @@ char* doubleToString( char* buf, size_t bufSize, double value, bool explicitZero
 
 int calcStructSize( const char* dt, int initial_size );
 int calcElemSize( const char* dt, int initial_size );
-char* encodeFormat( int elem_type, char* dt );
+CV_DEPRECATED char* encodeFormat( int elem_type, char* dt );
+char* encodeFormat( int elem_type, char* dt, size_t dt_len );
 int decodeFormat( const char* dt, int* fmt_pairs, int max_len );
 int decodeSimpleFormat( const char* dt );
 }
diff --git a/modules/core/src/persistence_types.cpp b/modules/core/src/persistence_types.cpp
index eeebdafe75..cd4fad05fb 100644
--- a/modules/core/src/persistence_types.cpp
+++ b/modules/core/src/persistence_types.cpp
@@ -10,14 +10,14 @@ namespace cv
 
 void write( FileStorage& fs, const String& name, const Mat& m )
 {
-    char dt[16];
+    char dt[22];
 
     if( m.dims <= 2 )
     {
         fs.startWriteStruct(name, FileNode::MAP, String("opencv-matrix"));
         fs << "rows" << m.rows;
         fs << "cols" << m.cols;
-        fs << "dt" << fs::encodeFormat( m.type(), dt );
+        fs << "dt" << fs::encodeFormat( m.type(), dt, sizeof(dt) );
         fs << "data" << "[:";
         for( int i = 0; i < m.rows; i++ )
             fs.writeRaw(dt, m.ptr(i), m.cols*m.elemSize());
@@ -30,7 +30,7 @@ void write( FileStorage& fs, const String& name, const Mat& m )
         fs << "sizes" << "[:";
         fs.writeRaw( "i", m.size.p, m.dims*sizeof(int) );
         fs << "]";
-        fs << "dt" << fs::encodeFormat( m.type(), dt );
+        fs << "dt" << fs::encodeFormat( m.type(), dt, sizeof(dt) );
         fs << "data" << "[:";
         const Mat* arrays[] = {&m, 0};
         uchar* ptrs[1] = {};
@@ -63,7 +63,7 @@ struct SparseNodeCmp
 
 void write( FileStorage& fs, const String& name, const SparseMat& m )
 {
-    char dt[16];
+    char dt[22];
 
     fs.startWriteStruct(name, FileNode::MAP, String("opencv-sparse-matrix"));
     fs << "sizes" << "[:";
@@ -71,7 +71,7 @@ void write( FileStorage& fs, const String& name, const SparseMat& m )
     if( dims > 0 )
         fs.writeRaw("i", m.hdr->size, dims*sizeof(int) );
     fs << "]";
-    fs << "dt" << fs::encodeFormat( m.type(), dt );
+    fs << "dt" << fs::encodeFormat( m.type(), dt, sizeof(dt) );
     fs << "data" << "[:";
 
     size_t i = 0, n = m.nzcount();
diff --git a/modules/core/src/persistence_xml.cpp b/modules/core/src/persistence_xml.cpp
index 2264d16baa..caba4f5bf0 100644
--- a/modules/core/src/persistence_xml.cpp
+++ b/modules/core/src/persistence_xml.cpp
@@ -208,7 +208,7 @@ public:
                     }
                     else
                     {
-                        sprintf( data, "#x%02x", (uchar)c );
+                        snprintf( data, sizeof(buf) - (data - buf), "#x%02x", (uchar)c );
                         data += 4;
                     }
                     *data++ = ';';
diff --git a/modules/core/src/persistence_yml.cpp b/modules/core/src/persistence_yml.cpp
index c8c7c7a892..e4f53c353e 100644
--- a/modules/core/src/persistence_yml.cpp
+++ b/modules/core/src/persistence_yml.cpp
@@ -152,7 +152,7 @@ public:
                         *data++ = 't';
                     else
                     {
-                        sprintf( data, "x%02x", c );
+                        snprintf( data, sizeof(buf) - (data - buf), "x%02x", c );
                         data += 3;
                     }
                 }
diff --git a/modules/core/src/sum.dispatch.cpp b/modules/core/src/sum.dispatch.cpp
index 20caca9f04..b01a7a2bd7 100644
--- a/modules/core/src/sum.dispatch.cpp
+++ b/modules/core/src/sum.dispatch.cpp
@@ -62,7 +62,7 @@ bool ocl_sum( InputArray _src, Scalar & res, int sum_op, InputArray _mask,
     wgs2_aligned >>= 1;
 
     static const char * const opMap[3] = { "OP_SUM", "OP_SUM_ABS", "OP_SUM_SQR" };
-    char cvt[2][40];
+    char cvt[2][50];
     String opts = format("-D srcT=%s -D srcT1=%s -D dstT=%s -D dstTK=%s -D dstT1=%s -D ddepth=%d -D cn=%d"
                          " -D convertToDT=%s -D %s -D WGS=%d -D WGS2_ALIGNED=%d%s%s%s%s -D kercn=%d%s%s%s -D convertFromU=%s",
                          ocl::typeToStr(CV_MAKE_TYPE(depth, mcn)), ocl::typeToStr(depth),
diff --git a/modules/core/src/umatrix.cpp b/modules/core/src/umatrix.cpp
index 846d406eca..ba958e646c 100644
--- a/modules/core/src/umatrix.cpp
+++ b/modules/core/src/umatrix.cpp
@@ -1259,7 +1259,7 @@ void UMat::convertTo(OutputArray _dst, int _type, double alpha, double beta) con
     {
         int wdepth = std::max(CV_32F, sdepth), rowsPerWI = 4;
 
-        char cvt[2][40];
+        char cvt[2][50];
         ocl::Kernel k("convertTo", ocl::core::convert_oclsrc,
                       format("-D srcT=%s -D WT=%s -D dstT=%s -D convertToWT=%s -D convertToDT=%s%s%s",
                              ocl::typeToStr(sdepth), ocl::typeToStr(wdepth), ocl::typeToStr(ddepth),
diff --git a/modules/core/test/test_mat.cpp b/modules/core/test/test_mat.cpp
index 9f4711a816..e39b16a1e5 100644
--- a/modules/core/test/test_mat.cpp
+++ b/modules/core/test/test_mat.cpp
@@ -497,7 +497,7 @@ static string idx2string(const int* idx, int dims)
     char* ptr = buf;
     for( int k = 0; k < dims; k++ )
     {
-        sprintf(ptr, "%4d ", idx[k]);
+        snprintf(ptr, sizeof(buf) - (ptr - buf), "%4d ", idx[k]);
         ptr += strlen(ptr);
     }
     ptr[-1] = '\0';
diff --git a/modules/highgui/src/window_w32.cpp b/modules/highgui/src/window_w32.cpp
index aad5b7db67..d2de2abeca 100644
--- a/modules/highgui/src/window_w32.cpp
+++ b/modules/highgui/src/window_w32.cpp
@@ -2030,7 +2030,7 @@ static void icvUpdateTrackbar(CvTrackbar& trackbar, int pos)
             memcpy(pos_text, trackbar.name.c_str(), name_len + 1);
         }
 
-        sprintf(pos_text + strlen(pos_text), "%s: %d\n", suffix, pos);
+        snprintf(pos_text + strlen(pos_text), sizeof(pos_text) - strlen(pos_text), "%s: %d\n", suffix, pos);
         SetWindowText(trackbar.buddy, pos_text);
     }
 }
diff --git a/modules/imgcodecs/src/grfmt_pam.cpp b/modules/imgcodecs/src/grfmt_pam.cpp
index 1c8f8476a5..979a31ca91 100644
--- a/modules/imgcodecs/src/grfmt_pam.cpp
+++ b/modules/imgcodecs/src/grfmt_pam.cpp
@@ -695,14 +695,14 @@ bool PAMEncoder::write( const Mat& img, const std::vector<int>& params )
 
     /* write header */
     tmp = 0;
-    tmp += sprintf( buffer, "P7\n");
-    tmp += sprintf( buffer + tmp, "WIDTH %d\n", width);
-    tmp += sprintf( buffer + tmp, "HEIGHT %d\n", height);
-    tmp += sprintf( buffer + tmp, "DEPTH %d\n", img.channels());
-    tmp += sprintf( buffer + tmp, "MAXVAL %d\n", (1 << img.elemSize1()*8) - 1);
+    tmp += snprintf( buffer, bufsize, "P7\n");
+    tmp += snprintf( buffer + tmp, bufsize - tmp, "WIDTH %d\n", width);
+    tmp += snprintf( buffer + tmp, bufsize - tmp, "HEIGHT %d\n", height);
+    tmp += snprintf( buffer + tmp, bufsize - tmp, "DEPTH %d\n", img.channels());
+    tmp += snprintf( buffer + tmp, bufsize - tmp, "MAXVAL %d\n", (1 << img.elemSize1()*8) - 1);
     if (fmt)
-        tmp += sprintf( buffer + tmp, "TUPLTYPE %s\n", fmt->name );
-    sprintf( buffer + tmp, "ENDHDR\n" );
+        tmp += snprintf( buffer + tmp, bufsize - tmp, "TUPLTYPE %s\n", fmt->name );
+    snprintf( buffer + tmp, bufsize - tmp, "ENDHDR\n" );
 
     strm.putBytes( buffer, (int)strlen(buffer) );
     /* write data */
diff --git a/modules/imgcodecs/src/grfmt_pxm.cpp b/modules/imgcodecs/src/grfmt_pxm.cpp
index c18ac7a1e2..8da2348728 100644
--- a/modules/imgcodecs/src/grfmt_pxm.cpp
+++ b/modules/imgcodecs/src/grfmt_pxm.cpp
@@ -467,12 +467,12 @@ bool PxMEncoder::write(const Mat& img, const std::vector<int>& params)
     const int code = ((mode == PXM_TYPE_PBM) ? 1 : (mode == PXM_TYPE_PGM) ? 2 : 3)
          + (isBinary ? 3 : 0);
 
-    int header_sz = sprintf(buffer, "P%c\n%d %d\n",
+    int header_sz = snprintf(buffer, bufferSize, "P%c\n%d %d\n",
             (char)('0' + code), width, height);
     CV_Assert(header_sz > 0);
     if (mode != PXM_TYPE_PBM)
     {
-        int sz = sprintf(&buffer[header_sz], "%d\n", (1 << depth) - 1);
+        int sz = snprintf(&buffer[header_sz], bufferSize - header_sz, "%d\n", (1 << depth) - 1);
         CV_Assert(sz > 0);
         header_sz += sz;
     }
@@ -560,11 +560,11 @@ bool PxMEncoder::write(const Mat& img, const std::vector<int>& params)
                     {
                         for( x = 0; x < width*channels; x += channels )
                         {
-                            sprintf( ptr, "% 4d", data[x + 2] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 4d", data[x + 2] );
                             ptr += 4;
-                            sprintf( ptr, "% 4d", data[x + 1] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 4d", data[x + 1] );
                             ptr += 4;
-                            sprintf( ptr, "% 4d", data[x] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 4d", data[x] );
                             ptr += 4;
                             *ptr++ = ' ';
                             *ptr++ = ' ';
@@ -574,11 +574,11 @@ bool PxMEncoder::write(const Mat& img, const std::vector<int>& params)
                     {
                         for( x = 0; x < width*channels; x += channels )
                         {
-                            sprintf( ptr, "% 6d", ((const ushort *)data)[x + 2] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 6d", ((const ushort *)data)[x + 2] );
                             ptr += 6;
-                            sprintf( ptr, "% 6d", ((const ushort *)data)[x + 1] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 6d", ((const ushort *)data)[x + 1] );
                             ptr += 6;
-                            sprintf( ptr, "% 6d", ((const ushort *)data)[x] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 6d", ((const ushort *)data)[x] );
                             ptr += 6;
                             *ptr++ = ' ';
                             *ptr++ = ' ';
@@ -591,7 +591,7 @@ bool PxMEncoder::write(const Mat& img, const std::vector<int>& params)
                     {
                         for( x = 0; x < width; x++ )
                         {
-                            sprintf( ptr, "% 4d", data[x] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 4d", data[x] );
                             ptr += 4;
                         }
                     }
@@ -599,7 +599,7 @@ bool PxMEncoder::write(const Mat& img, const std::vector<int>& params)
                     {
                         for( x = 0; x < width; x++ )
                         {
-                            sprintf( ptr, "% 6d", ((const ushort *)data)[x] );
+                            snprintf( ptr, bufferSize - (ptr - buffer), "% 6d", ((const ushort *)data)[x] );
                             ptr += 6;
                         }
                     }
diff --git a/modules/imgproc/src/accum.cpp b/modules/imgproc/src/accum.cpp
index fbd5223c13..3ef958e0cb 100644
--- a/modules/imgproc/src/accum.cpp
+++ b/modules/imgproc/src/accum.cpp
@@ -126,7 +126,7 @@ static bool ocl_accumulate( InputArray _src, InputArray _src2, InputOutputArray
     const char * const opMap[4] = { "ACCUMULATE", "ACCUMULATE_SQUARE", "ACCUMULATE_PRODUCT",
                                    "ACCUMULATE_WEIGHTED" };
 
-    char cvt[40];
+    char cvt[50];
     ocl::Kernel k("accumulate", ocl::imgproc::accumulate_oclsrc,
                   format("-D %s%s -D srcT1=%s -D cn=%d -D dstT1=%s%s -D rowsPerWI=%d -D convertToDT=%s",
                          opMap[op_type], haveMask ? " -D HAVE_MASK" : "",
diff --git a/modules/imgproc/src/bilateral_filter.dispatch.cpp b/modules/imgproc/src/bilateral_filter.dispatch.cpp
index ed0e71bbab..b3c8388448 100644
--- a/modules/imgproc/src/bilateral_filter.dispatch.cpp
+++ b/modules/imgproc/src/bilateral_filter.dispatch.cpp
@@ -111,7 +111,7 @@ static bool ocl_bilateralFilter_8u(InputArray _src, OutputArray _dst, int d,
             space_ofs[maxk++] = (int)(i * temp.step + j * cn);
         }
 
-    char cvt[3][40];
+    char cvt[3][50];
     String cnstr = cn > 1 ? format("%d", cn) : "";
     String kernelName("bilateral");
     size_t sizeDiv = 1;
diff --git a/modules/imgproc/src/blend.cpp b/modules/imgproc/src/blend.cpp
index e0ee9ec0c5..2ed28cea2b 100644
--- a/modules/imgproc/src/blend.cpp
+++ b/modules/imgproc/src/blend.cpp
@@ -350,7 +350,7 @@ static bool ocl_blendLinear( InputArray _src1, InputArray _src2, InputArray _wei
 {
     int type = _src1.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type);
 
-    char cvt[30];
+    char cvt[50];
     ocl::Kernel k("blendLinear", ocl::imgproc::blend_linear_oclsrc,
                   format("-D T=%s -D cn=%d -D convertToT=%s", ocl::typeToStr(depth),
                          cn, ocl::convertTypeStr(CV_32F, depth, 1, cvt)));
diff --git a/modules/imgproc/src/box_filter.dispatch.cpp b/modules/imgproc/src/box_filter.dispatch.cpp
index 698f2ae2fb..0856d9e545 100644
--- a/modules/imgproc/src/box_filter.dispatch.cpp
+++ b/modules/imgproc/src/box_filter.dispatch.cpp
@@ -195,7 +195,7 @@ static bool ocl_boxFilter( InputArray _src, OutputArray _dst, int ddepth,
         const int wgRound = 256;
         globalsize[0] = roundUp(globalsize[0], wgRound);
 
-        char build_options[1024], cvt[2][40];
+        char build_options[1024], cvt[2][50];
         snprintf(build_options, sizeof(build_options), "-D cn=%d "
                 "-D ANCHOR_X=%d -D ANCHOR_Y=%d -D KERNEL_SIZE_X=%d -D KERNEL_SIZE_Y=%d "
                 "-D PX_LOAD_VEC_SIZE=%d -D PX_LOAD_NUM_PX=%d "
diff --git a/modules/imgproc/src/canny.cpp b/modules/imgproc/src/canny.cpp
index d845de33f1..e64d1c469c 100644
--- a/modules/imgproc/src/canny.cpp
+++ b/modules/imgproc/src/canny.cpp
@@ -183,7 +183,7 @@ static bool ocl_Canny(InputArray _src, const UMat& dx_, const UMat& dy_, OutputA
                 Non maxima suppression
                 Double thresholding
         */
-        char cvt[40];
+        char cvt[50];
         ocl::Kernel with_sobel("stage1_with_sobel", ocl::imgproc::canny_oclsrc,
                                format("-D WITH_SOBEL -D cn=%d -D TYPE=%s -D convert_floatN=%s -D floatN=%s -D GRP_SIZEX=%d -D GRP_SIZEY=%d%s",
                                       cn, ocl::memopTypeToStr(_src.depth()),
diff --git a/modules/imgproc/src/deriv.cpp b/modules/imgproc/src/deriv.cpp
index fb7e7786f5..419d867ae8 100644
--- a/modules/imgproc/src/deriv.cpp
+++ b/modules/imgproc/src/deriv.cpp
@@ -578,7 +578,7 @@ static bool ocl_Laplacian5(InputArray _src, OutputArray _dst,
         size_t lt2[2] = { tileSizeX, tileSizeY};
         size_t gt2[2] = { lt2[0] * (1 + (size.width - 1) / lt2[0]), lt2[1] };
 
-        char cvt[2][40];
+        char cvt[2][50];
         const char * const borderMap[] = { "BORDER_CONSTANT", "BORDER_REPLICATE", "BORDER_REFLECT", "BORDER_WRAP",
                                            "BORDER_REFLECT_101" };
 
@@ -624,7 +624,7 @@ static bool ocl_Laplacian5(InputArray _src, OutputArray _dst,
     if (!doubleSupport && wdepth == CV_64F)
         return false;
 
-    char cvt[2][40];
+    char cvt[2][50];
     ocl::Kernel k("sumConvert", ocl::imgproc::laplacian5_oclsrc,
                   format("-D ONLY_SUM_CONVERT "
                          "-D srcT=%s -D WT=%s -D dstT=%s -D coeffT=%s -D wdepth=%d "
diff --git a/modules/imgproc/src/filter.dispatch.cpp b/modules/imgproc/src/filter.dispatch.cpp
index 53b8bb42c4..850fb31126 100644
--- a/modules/imgproc/src/filter.dispatch.cpp
+++ b/modules/imgproc/src/filter.dispatch.cpp
@@ -590,7 +590,7 @@ static bool ocl_filter2D( InputArray _src, OutputArray _dst, int ddepth,
     size_t tryWorkItems = device.maxWorkGroupSize();
     if (device.isIntel() && 128 < tryWorkItems)
         tryWorkItems = 128;
-    char cvt[2][40];
+    char cvt[2][50];
 
     // For smaller filter kernels, there is a special kernel that is more
     // efficient than the general one.
@@ -764,7 +764,7 @@ static bool ocl_sepRowFilter2D(const UMat & src, UMat & buf, const Mat & kernelX
     extra_extrapolation |= src.cols < (int)((-radiusX + globalsize[0] + 8 * localsize[0] + 3) >> 1) + 1;
     extra_extrapolation |= src.cols < radiusX;
 
-    char cvt[40];
+    char cvt[50];
     cv::String build_options = cv::format("-D RADIUSX=%d -D LSIZE0=%d -D LSIZE1=%d -D CN=%d -D %s -D %s -D %s"
                                           " -D srcT=%s -D dstT=%s -D convertToDstT=%s -D srcT1=%s -D dstT1=%s%s%s",
                                           radiusX, (int)localsize[0], (int)localsize[1], cn, btype,
@@ -825,7 +825,7 @@ static bool ocl_sepColFilter2D(const UMat & buf, UMat & dst, const Mat & kernelY
     globalsize[1] = DIVUP(sz.height, localsize[1]) * localsize[1];
     globalsize[0] = DIVUP(sz.width, localsize[0]) * localsize[0];
 
-    char cvt[2][40];
+    char cvt[2][50];
     int floatT = std::max(CV_32F, bdepth);
     cv::String build_options = cv::format("-D RADIUSY=%d -D LSIZE0=%d -D LSIZE1=%d -D CN=%d"
                                           " -D srcT=%s -D dstT=%s -D convertToFloatT=%s -D floatT=%s -D convertToDstT=%s"
@@ -891,7 +891,7 @@ static bool ocl_sepFilter2D_SinglePass(InputArray _src, OutputArray _dst,
     size_t lt2[2] = { optimizedSepFilterLocalWidth, optimizedSepFilterLocalHeight };
     size_t gt2[2] = { lt2[0] * (1 + (size.width - 1) / lt2[0]), lt2[1]};
 
-    char cvt[2][40];
+    char cvt[2][50];
     const char * const borderMap[] = { "BORDER_CONSTANT", "BORDER_REPLICATE", "BORDER_REFLECT", "BORDER_WRAP",
                                        "BORDER_REFLECT_101" };
 
diff --git a/modules/imgproc/src/histogram.cpp b/modules/imgproc/src/histogram.cpp
index 84a2734eae..9cdd6b945f 100644
--- a/modules/imgproc/src/histogram.cpp
+++ b/modules/imgproc/src/histogram.cpp
@@ -1232,7 +1232,7 @@ static bool ocl_calcHist1(InputArray _src, OutputArray _hist, int ddepth = CV_32
         return false;
 
     wgs = std::min<size_t>(ocl::Device::getDefault().maxWorkGroupSize(), BINS);
-    char cvt[40];
+    char cvt[50];
     ocl::Kernel k2("merge_histogram", ocl::imgproc::histogram_oclsrc,
                    format("-D BINS=%d -D HISTS_COUNT=%d -D WGS=%d -D convertToHT=%s -D HT=%s",
                           BINS, compunits, (int)wgs, ocl::convertTypeStr(CV_32S, ddepth, 1, cvt),
diff --git a/modules/imgproc/src/imgwarp.cpp b/modules/imgproc/src/imgwarp.cpp
index c36c8cebf5..efb56dd95f 100644
--- a/modules/imgproc/src/imgwarp.cpp
+++ b/modules/imgproc/src/imgwarp.cpp
@@ -1340,7 +1340,7 @@ static bool ocl_remap(InputArray _src, OutputArray _dst, InputArray _map1, Input
 
     if (interpolation != INTER_NEAREST)
     {
-        char cvt[3][40];
+        char cvt[3][50];
         int wdepth = std::max(CV_32F, depth);
         buildOptions = buildOptions
                       + format(" -D WT=%s -D convertToT=%s -D convertToWT=%s"
diff --git a/modules/imgproc/src/morph.dispatch.cpp b/modules/imgproc/src/morph.dispatch.cpp
index 45ae3994d9..5c296dffe4 100644
--- a/modules/imgproc/src/morph.dispatch.cpp
+++ b/modules/imgproc/src/morph.dispatch.cpp
@@ -617,7 +617,7 @@ static bool ocl_morphSmall( InputArray _src, OutputArray _dst, InputArray _kerne
         wdepth = CV_32S;
         wtype = CV_MAKETYPE(wdepth, cn);
     }
-    char cvt[2][40];
+    char cvt[2][50];
 
     const char * const borderMap[] = { "BORDER_CONSTANT", "BORDER_REPLICATE",
                                        "BORDER_REFLECT", 0, "BORDER_REFLECT_101" };
diff --git a/modules/imgproc/src/resize.cpp b/modules/imgproc/src/resize.cpp
index f388587f9c..8ab2b206ca 100644
--- a/modules/imgproc/src/resize.cpp
+++ b/modules/imgproc/src/resize.cpp
@@ -3305,7 +3305,7 @@ static bool ocl_resize( InputArray _src, OutputArray _dst, Size dsize,
     if (useSampler)
     {
         int wdepth = std::max(depth, CV_32S);
-        char buf[2][32];
+        char buf[2][50];
         cv::String compileOpts = format("-D USE_SAMPLER -D depth=%d -D T=%s -D T1=%s "
                         "-D convertToDT=%s -D cn=%d",
                         depth, ocl::typeToStr(type), ocl::typeToStr(depth),
@@ -3327,7 +3327,7 @@ static bool ocl_resize( InputArray _src, OutputArray _dst, Size dsize,
 
     if (interpolation == INTER_LINEAR && !useSampler)
     {
-        char buf[2][32];
+        char buf[2][50];
 
         // integer path is slower because of CPU part, so it's disabled
         if (depth == CV_8U && ((void)0, 0))
@@ -3419,7 +3419,7 @@ static bool ocl_resize( InputArray _src, OutputArray _dst, Size dsize,
         int wdepth = std::max(depth, is_area_fast ? CV_32S : CV_32F);
         int wtype = CV_MAKE_TYPE(wdepth, cn);
 
-        char cvt[2][40];
+        char cvt[2][50];
         String buildOption = format("-D INTER_AREA -D T=%s -D T1=%s -D WTV=%s -D convertToWTV=%s -D cn=%d",
                                     ocl::typeToStr(type), ocl::typeToStr(depth), ocl::typeToStr(wtype),
                                     ocl::convertTypeStr(depth, wdepth, cn, cvt[0]), cn);
diff --git a/modules/imgproc/src/templmatch.cpp b/modules/imgproc/src/templmatch.cpp
index 6b192d775f..edf214385e 100644
--- a/modules/imgproc/src/templmatch.cpp
+++ b/modules/imgproc/src/templmatch.cpp
@@ -87,7 +87,7 @@ static bool sumTemplate(InputArray _src, UMat & result)
         wgs2_aligned <<= 1;
     wgs2_aligned >>= 1;
 
-    char cvt[40];
+    char cvt[50];
     ocl::Kernel k("calcSum", ocl::imgproc::match_template_oclsrc,
                   format("-D CALC_SUM -D T=%s -D T1=%s -D WT=%s -D cn=%d -D convertToWT=%s -D WGS=%d -D WGS2_ALIGNED=%d",
                          ocl::typeToStr(type), ocl::typeToStr(depth), ocl::typeToStr(wtype), cn,
@@ -268,8 +268,8 @@ static bool matchTemplateNaive_CCORR(InputArray _image, InputArray _templ, Outpu
         wtype1 = CV_MAKE_TYPE(wdepth, rated_cn);
     }
 
-    char cvt[40];
-    char cvt1[40];
+    char cvt[50];
+    char cvt1[50];
     const char* convertToWT1 = ocl::convertTypeStr(depth, wdepth, cn, cvt);
     const char* convertToWT = ocl::convertTypeStr(depth, wdepth, rated_cn, cvt1);
 
@@ -349,7 +349,7 @@ static bool matchTemplateNaive_SQDIFF(InputArray _image, InputArray _templ, Outp
     int type = _image.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type);
     int wdepth = CV_32F, wtype = CV_MAKE_TYPE(wdepth, cn);
 
-    char cvt[40];
+    char cvt[50];
     ocl::Kernel k("matchTemplate_Naive_SQDIFF", ocl::imgproc::match_template_oclsrc,
                   format("-D SQDIFF -D T=%s -D T1=%s -D WT=%s -D convertToWT=%s -D cn=%d", ocl::typeToStr(type), ocl::typeToStr(depth),
                          ocl::typeToStr(wtype), ocl::convertTypeStr(depth, wdepth, cn, cvt), cn));
diff --git a/modules/photo/src/fast_nlmeans_denoising_opencl.hpp b/modules/photo/src/fast_nlmeans_denoising_opencl.hpp
index cb3327d392..0788a47964 100644
--- a/modules/photo/src/fast_nlmeans_denoising_opencl.hpp
+++ b/modules/photo/src/fast_nlmeans_denoising_opencl.hpp
@@ -57,7 +57,7 @@ static bool ocl_calcAlmostDist2Weight(UMat & almostDist2Weight,
 
     almostDist2Weight.create(1, almostMaxDist, CV_32SC(hn == 3 ? 4 : hn));
 
-    char buf[40];
+    char buf[50];
     ocl::Kernel k("calcAlmostDist2Weight", ocl::photo::nlmeans_oclsrc,
                   format("-D OP_CALC_WEIGHTS -D FT=%s -D w_t=%s"
                          " -D wlut_t=%s -D convert_wlut_t=%s%s%s",