40 lines
1,012 B
PHP
40 lines
1,012 B
PHP
--TEST--
|
|
GH-20584 (Information Leak of Memory)
|
|
--CREDITS--
|
|
Nikita Sveshnikov (Positive Technologies)
|
|
--FILE--
|
|
<?php
|
|
// Minimal PoC: corruption/uninitialized memory leak when reading APP1 via php://filter
|
|
$file = __DIR__ . '/gh20584.jpg';
|
|
|
|
// Make APP1 large enough so it is read in multiple chunks
|
|
$chunk = 8192;
|
|
$tail = 123;
|
|
$payload = str_repeat('A', $chunk) . str_repeat('B', $chunk) . str_repeat('Z',
|
|
$tail);
|
|
$app1Len = 2 + strlen($payload);
|
|
|
|
// Minimal JPEG: SOI + APP1 + SOF0(1x1) + EOI
|
|
$sof = "\xFF\xC0" . pack('n', 11) . "\x08" . pack('n',1) . pack('n',1) .
|
|
"\x01\x11\x00";
|
|
$jpeg = "\xFF\xD8" . "\xFF\xE1" . pack('n', $app1Len) . $payload . $sof .
|
|
"\xFF\xD9";
|
|
file_put_contents($file, $jpeg);
|
|
|
|
// Read through a filter to enforce multiple reads
|
|
$src = 'php://filter/read=string.rot13|string.rot13/resource=' . $file;
|
|
$info = null;
|
|
@getimagesize($src, $info);
|
|
$exp = $payload;
|
|
$ret = $info['APP1'];
|
|
|
|
var_dump($ret === $exp);
|
|
|
|
?>
|
|
--CLEAN--
|
|
<?php
|
|
@unlink(__DIR__ . '/gh20584.jpg');
|
|
?>
|
|
--EXPECT--
|
|
bool(true)
|