diff options
Diffstat (limited to 'wp-admin/includes/class-pclzip.php')
| -rw-r--r-- | wp-admin/includes/class-pclzip.php | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/wp-admin/includes/class-pclzip.php b/wp-admin/includes/class-pclzip.php index d387f00..b490744 100644 --- a/wp-admin/includes/class-pclzip.php +++ b/wp-admin/includes/class-pclzip.php @@ -4470,7 +4470,9 @@ $v_byte = @fread($this->zip_fd, 1); // ----- Add the byte - $v_bytes = ($v_bytes << 8) | Ord($v_byte); + // Note we mask the old value down such that once shifted we can never end up with more than a 32bit number + // Otherwise on systems where we have 64bit integers the check below for the magic number will fail. + $v_bytes = ( ($v_bytes & 0xFFFFFF) << 8) | Ord($v_byte); // ----- Compare the bytes if ($v_bytes == 0x504b0506) |