diff --git a/ext/phar/dirstream.c b/ext/phar/dirstream.c
index 75cf049adef..94958a26aaf 100644
--- a/ext/phar/dirstream.c
+++ b/ext/phar/dirstream.c
@@ -207,6 +207,7 @@ static php_stream *phar_make_dirstream(char *dir, HashTable *manifest TSRMLS_DC)
 	zend_hash_internal_pointer_reset(manifest);
 
 	while (FAILURE != zend_hash_has_more_elements(manifest)) {
+		keylen = 0;
 		if (HASH_KEY_NON_EXISTENT == zend_hash_get_current_key_ex(manifest, &key, &keylen, &unused, 0, NULL)) {
 			break;
 		}
@@ -214,7 +215,7 @@ static php_stream *phar_make_dirstream(char *dir, HashTable *manifest TSRMLS_DC)
 		PHAR_STR(key, str_key);
 
 		if (keylen <= (uint)dirlen) {
-			if (keylen < (uint)dirlen || !strncmp(str_key, dir, dirlen)) {
+			if (keylen == 0 || keylen < (uint)dirlen || !strncmp(str_key, dir, dirlen)) {
 				PHAR_STR_FREE(str_key);
 				if (SUCCESS != zend_hash_move_forward(manifest)) {
 					break;
diff --git a/ext/phar/tar.c b/ext/phar/tar.c
index 3a4bd491f8c..bf19e08ac09 100644
--- a/ext/phar/tar.c
+++ b/ext/phar/tar.c
@@ -356,7 +356,7 @@ bail:
 			entry.filename_len = entry.uncompressed_filesize;
 
 			/* Check for overflow - bug 61065 */
-			if (entry.filename_len == UINT_MAX) {
+			if (entry.filename_len == UINT_MAX || entry.filename_len == 0) {
 				if (error) {
 					spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (invalid entry size)", fname);
 				}
diff --git a/ext/phar/tests/bug71331.phpt b/ext/phar/tests/bug71331.phpt
new file mode 100644
index 00000000000..106fd540fc3
--- /dev/null
+++ b/ext/phar/tests/bug71331.phpt
@@ -0,0 +1,15 @@
+--TEST--
+Bug #71331 (Uninitialized pointer in phar_make_dirstream())
+--SKIPIF--
+<?php if (!extension_loaded("phar")) die("skip"); ?>
+--FILE--
+<?php
+$p = new PharData(__DIR__."/bug71331.tar");
+?>
+DONE
+--EXPECTF--
+Fatal error: Uncaught exception 'UnexpectedValueException' with message 'phar error: "%s/bug71331.tar" is a corrupted tar file (invalid entry size)' in %s/bug71331.php:2
+Stack trace:
+#0 %s/bug71331.php(2): PharData->__construct('%s')
+#1 {main}
+  thrown in %s/bug71331.php on line 2
\ No newline at end of file
diff --git a/ext/phar/tests/bug71331.tar b/ext/phar/tests/bug71331.tar
new file mode 100644
index 00000000000..14eec28781e
Binary files /dev/null and b/ext/phar/tests/bug71331.tar differ