diff --git a/src/file_exe.c b/src/file_exe.c
index fab7e18f..819cc695 100644
--- a/src/file_exe.c
+++ b/src/file_exe.c
@@ -119,7 +119,10 @@ static int header_check_exe(const unsigned char *buffer, const unsigned int buff
       uint64_t sum=0;
       const struct pe_image_section_hdr *pe_image_section=(const struct pe_image_section_hdr*)
 	((const unsigned char*)pe_hdr + sizeof(struct pe_image_file_hdr) + le16(pe_hdr->SizeOfOptionalHeader));
-      for(i=0;i<le16(pe_hdr->NumberOfSections) && (const unsigned char*)pe_image_section < buffer+buffer_size;i++,pe_image_section++)
+      for(i=0;
+	  i<le16(pe_hdr->NumberOfSections) &&
+	  (const unsigned char*)(pe_image_section+1) <= buffer+buffer_size;
+	  i++,pe_image_section++)
       {
 	if(le32(pe_image_section->SizeOfRawData)>0)
 	{
diff --git a/src/file_fits.c b/src/file_fits.c
index a82e4386..606772fd 100644
--- a/src/file_fits.c
+++ b/src/file_fits.c
@@ -71,7 +71,7 @@ static uint64_t fits_info(const unsigned char *buffer, const unsigned int buffer
   uint64_t naxis_size=1;
   unsigned int i=*i_pointer;
   /* Header is composed of 80 character fixed-length strings */
-  for(; i<buffer_size &&
+  for(; i+80 < buffer_size &&
       memcmp(&buffer[i], "END ", 4)!=0;
       i+=80)
   {
diff --git a/src/file_jpg.c b/src/file_jpg.c
index 261be27d..8c8ae088 100644
--- a/src/file_jpg.c
+++ b/src/file_jpg.c
@@ -1349,7 +1349,7 @@ static int jpg_check_dht(const unsigned char *buffer, const unsigned int buffer_
       return 2;
     j++;
     for(l=0; l < 16; l++)
-      if(j < buffer_size)
+      if(j+l < buffer_size)
 	sum+=buffer[j+l];
     if(sum>255)
       return 2;
diff --git a/src/file_mp3.c b/src/file_mp3.c
index cddcbb02..9cde9476 100644
--- a/src/file_mp3.c
+++ b/src/file_mp3.c
@@ -367,7 +367,9 @@ static data_check_t data_check_mp3(const unsigned char *buffer, const unsigned i
 static unsigned int pos_in_mem(const unsigned char *haystack, const unsigned int haystack_size, const unsigned char *needle, const unsigned int needle_size)
 {
   unsigned int i;
-  for(i=0;i<haystack_size;i++)
+  if(haystack_size < needle_size)
+    return 0;
+  for(i=0; i <= haystack_size - needle_size; i++)
     if(memcmp(&haystack[i],needle,needle_size)==0)
       return (i+needle_size);
   return 0;
diff --git a/src/file_riff.c b/src/file_riff.c
index f6cc5caf..dedc297c 100644
--- a/src/file_riff.c
+++ b/src/file_riff.c
@@ -259,7 +259,7 @@ static int header_check_riff(const unsigned char *buffer, const unsigned int buf
     reset_file_recovery(file_recovery_new);
     file_recovery_new->extension="avi";
     /* Is it a raw avi stream with Data Binary chunks ? */
-    if(size + 4 < buffer_size &&
+    if(size < buffer_size - 4 &&
 	memcmp(&buffer[size - sizeof(list_movi)], &list_movi, sizeof(list_movi)) ==0 &&
 	buffer[size+2]=='d' &&
 	buffer[size+3]=='b')
diff --git a/src/file_zip.c b/src/file_zip.c
index 68f24313..a9dfe925 100644
--- a/src/file_zip.c
+++ b/src/file_zip.c
@@ -880,7 +880,9 @@ static int header_check_winzip(const unsigned char *buffer, const unsigned int b
 static unsigned int pos_in_mem(const unsigned char *haystack, const unsigned int haystack_size, const unsigned char *needle, const unsigned int needle_size)
 {
   unsigned int i;
-  for(i=0;i<haystack_size;i++)
+  if(haystack_size < needle_size)
+    return 0;
+  for(i=0; i <= haystack_size - needle_size; i++)
     if(memcmp(&haystack[i],needle,needle_size)==0)
       return (i+needle_size);
   return 0;