diff --git a/ext/exif/exif.c b/ext/exif/exif.c
index 1147980f773..cad29b72954 100644
--- a/ext/exif/exif.c
+++ b/ext/exif/exif.c
@@ -2728,6 +2728,7 @@ static int exif_process_IFD_in_MAKERNOTE(image_info_type *ImageInfo, char * valu
 	int NumDirEntries, old_motorola_intel, offset_diff;
 	const maker_note_type *maker_note;
 	char *dir_start;
+	int data_len;
 
 	for (i=0; i<=sizeof(maker_note_array)/sizeof(maker_note_type); i++) {
 		if (i==sizeof(maker_note_array)/sizeof(maker_note_type)) {
@@ -2782,6 +2783,7 @@ static int exif_process_IFD_in_MAKERNOTE(image_info_type *ImageInfo, char * valu
 	switch (maker_note->offset_mode) {
 		case MN_OFFSET_MAKER:
 			offset_base = value_ptr;
+			data_len = value_len;
 			break;
 		case MN_OFFSET_GUESS:
 			if (maker_note->offset + 10 + 4 >= value_len) {
@@ -2798,6 +2800,7 @@ static int exif_process_IFD_in_MAKERNOTE(image_info_type *ImageInfo, char * valu
 				return FALSE;
 			}
 			offset_base = value_ptr + offset_diff;
+			data_len = value_len - offset_diff;
 			break;
 		default:
 		case MN_OFFSET_NORMAL:
@@ -2811,7 +2814,7 @@ static int exif_process_IFD_in_MAKERNOTE(image_info_type *ImageInfo, char * valu
 
 	for (de=0;de<NumDirEntries;de++) {
 		if (!exif_process_IFD_TAG(ImageInfo, dir_start + 2 + 12 * de,
-								  offset_base, IFDlength, displacement, section_index, 0, maker_note->tag_table TSRMLS_CC)) {
+								  offset_base, data_len, displacement, section_index, 0, maker_note->tag_table TSRMLS_CC)) {
 			return FALSE;
 		}
 	}
diff --git a/ext/exif/tests/bug76557.jpg b/ext/exif/tests/bug76557.jpg
new file mode 100644
index 00000000000..d678f07c0fd
Binary files /dev/null and b/ext/exif/tests/bug76557.jpg differ
diff --git a/ext/exif/tests/bug76557.phpt b/ext/exif/tests/bug76557.phpt
new file mode 100644
index 00000000000..4553b627723
--- /dev/null
+++ b/ext/exif/tests/bug76557.phpt
@@ -0,0 +1,79 @@
+--TEST--
+Bug 76557 (heap-buffer-overflow (READ of size 48) while reading exif data)
+--SKIPIF--
+<?php if (!extension_loaded('exif')) print 'skip exif extension not available';?>
+--FILE--
+<?php
+var_dump(count(exif_read_data(dirname(__FILE__) . "/bug76557.jpg")));
+?>
+DONE
+--EXPECTF--
+Warning: exif_read_data(bug76557.jpg): Process tag(x010F=Make       ): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x8769=Exif_IFD_Po): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x927C=MakerNote  ): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal format code 0x3030, suppose BYTE in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Process tag(x3030=UndefinedTa): Illegal pointer offset(x30303030 + x30303030 = x60606060 > x00EE) in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): File structure corrupted in %sbug76557.php on line %d
+
+Warning: exif_read_data(bug76557.jpg): Invalid JPEG file in %sbug76557.php on line %d
+int(1)
+DONE