Network – How to bypass the output traffic filtering for an inverted shell?

Let's say that I have access to a Linux server as a non-root user (RCE acquired with an exploit), say that I can only execute commands via http in bash / sh but I can not make sure that the targeted server reconnects to a server. remote server listening for connections.

How could I establish a reverse shell connection if there are output filters on the targeted server? Is there a way around using DNS tunnels etc? How could I achieve this just with netcat or bash?

package management – E: the subprocess / usr / bin / dpkg returned an error code (1) – but how can I find the significant error messages in the output of APT?

In the complete output of sudo apt update or sudo apt upgrade or sudo apt install -f you should find messages from dpkg about what really went wrong.

These lines will start with dpkg: since it is the name of the program returning the error. Exit lines immediately preceding or following these lines are often the most useful.


Some examples of the many possible mistakes you might see:

Setting up install-info (6.4.90.dfsg.1-1build1) ...
/usr/sbin/update-info-dir: 3: /etc/environment: $: not found
dpkg: error processing package install-info (--configure):
    subprocess installed post-installation script returned error exit status 127

This means that the post-installation script could not be executed. In reality, 127 In Bash, the command is not found. A command called by the postinst script is not found. The lines before the dpkg line gives a probable reason – there is no /etc/environment file to set the PATH variable so that the shell that runs the script does not look for the necessary commands in the right places.

start: Unable to connect to Upstart: Failed to connect to socket /com/ubuntu/upstart: Connection refused
No apport report written because the error message indicates its a followup error from a previous failure.
dpkg: error processing package runit (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of git-daemon-run:
 git-daemon-run depends on runit; however:
  Package runit is not configured yet.

The above error was caused by a bug in the runit package, which should find installed Upstart, although systemd succeeded it as the default init system for Ubuntu. So the message failed to connect to Upstart is the best clue, but we need context to know how this causes the package management problem.

Unpacking libjline-java (from .../libjline-java_1.0-1_all.deb) ...
dpkg: error processing /var/cache/apt/archives/libjline-java_1.0-1_all.deb (--unpack):
 trying to overwrite '/usr/share/java/jline.jar', which is also in package scala 2.9.2-400

This means that there are package conflicts, perhaps due to the mix of repository versions or third-party repositories.


TL; DR

In any case where you see the error Sub-process /usr/bin/dpkg returned an error code (1), you must search above the lines starting with dpkg: and the lines before and after them for useful clues about what went wrong. Try to look for these specific mistakes.

If you're asking a question here or on another support site, make sure to include the order you've run and the completed output, not just the summary error messages.

output – Example with $ CharacterEncoding

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script – Wolframscript – no command output when executed from php

I'm trying to run a simple command via php:

echo shell_exec('wolframscript -code 2+2');

However, I can not get output from this command when it is executed like this. If I just write the same thing in cmd / powershell, it works fine.

I'm using v12, on windows, php7.3.

neural networks – form mlp (input x, output) with a black box labeling any x-y pair good / bad

The standard MLP (map x to y) is formed with a set of x-y data points.

My question: what happens if there is no train data, the only supervisor identifies an xy pair with 0 or 1. The goal is that the xy pair generated by the MLP always be labeled 0. How to form the MLP?

No DispalyPort Option in the Audio Output Device Menu, Nvidia Drivers

I can not display my monitor connected to DisplayPort (AW2518HF, connected external speakers) in this drop-down menu:
Settings> Sound> Output> Output Device.

I have opened the Nvidia X server settings and I can assure you that DP Audio is enabled. In addition, I started Windows 7 and was able to select it and play a perfect sound.

I'm using a GTX 750 (EVGA; they've added a DP port in their version) with the 418 driver installed from Software & Updates on Ubuntu 19.04.

here is aplay -l

**** List of PLAYBACK Hardware Devices ****
card 0: PCH (HDA Intel PCH), device 0: ALC887-VD Analog (ALC887-VD Analog)
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia (HDA NVidia), device 3: HDMI 0 (HDMI 0)
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia (HDA NVidia), device 7: HDMI 1 (HDMI 1)
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia (HDA NVidia), device 8: HDMI 2 (HDMI 2)
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Unformatted view and output of the custom taxonomy field

The initial problem I had was to set up a taxonomy called Category. I added vocabulary to my category taxonomy. Some of the terms I've added contain spaces. Labels should have spaces, so I want to keep them. I want to remove spaces from the category name when they are displayed in the view, unformatted, based on templates.

This would solve all my problems if I could extract these spaces from category names. I've set up a custom field on taxonomy terms to handle this, but I do not know how to access the custom fields of the taxonomy term from the view-view-unformatted.html.twig template. Is there a pre-processing function that can do this? Something where I can convert the category and just delete the spaces or change the label output value to field_nospace_category?

More experimentation

I've configured a page-like view to display articles in my Articles content type. I'm using the unformatted list and I've created a custom template called views-view-unformatted – my_view_id.html.twig. I see that it is the model that comes out on my page.

I'm trying to get out the custom field of taxonomy terms as a class on the div that has {{row.attributes.addClass (row_classes)}}

The div should look like this:

I've tried several variants to try to get the values. Inside the loop for row in rows, I put:

{{ node.category.entity.field_category.value }}
{{ row.content('#node').field_category.getValue().0.target_id }}
{{field_category}}
{{row.content('#elements').field_category.getValue().0.target_id}}

I've tried debugging using Kint, Dump but my installation continues to generate errors (insufficient memory) or a blank blank page.

Please help. Thank you in advance.

icmp – nmap – get a detailed output for requests?

when I run

nmap -sn

to probe a specific host, nmap returns "Host is up" even if ICMP is completely blocked for the server I've polled. I guess the message "Host is up" is based on an ICMP response (as it's the open channel I know), based on the nmap documentation:

The default host discovery performed with -sn includes an ICMP echo request, TCP SYN on port 443, TCP ACK on port 80, and an ICMP default time stamp request.

Now, I'm wondering if it's possible to have nmap tell me WHY the host is active, for example. get a commented exit for the simple steps involved in the survey. I've tried to run it with -v, but that only gives a general version and speech. '

I know I could do the simple queries myself (for example: hping3), but I'm particularly interested in the possibility that it's possible with nmap, because I'm linked to a Windows machine here (and WSL still does not take support the necessary raw sockets.

Thank you.

Change the output format json to rails?

I have an API that has the data in the following format:

(
{
    "id": 1,
    "vehicle": "350",
    "code": "350",
    "delivery_date": "2019-07-26T00:00:00.000Z",
    "created_at": "2019-08-07T17:00:37.000Z",
    "updated_at": "2019-08-07T17:00:37.000Z"
},
{
    "id": 2,
    "vehicle": "364",
    "code": "364",
    "delivery_date": "2019-07-26T00:00:00.000Z",
    "created_at": "2019-08-07T17:00:37.000Z",
    "updated_at": "2019-08-07T17:00:37.000Z"
},
{
    "id": 3,
    "vehicle": "1305",
    "code": "1305",
    "delivery_date": "2019-07-26T00:00:00.000Z",
    "created_at": "2019-08-07T17:00:37.000Z",
    "updated_at": "2019-08-07T17:00:37.000Z"
},
)

The fact is that because of (I think) the "()" I can not do the research
url / api / loads / list /1

So, how can I change this output?

@loads = Load.all
        render json: @loads, status: 200

That's what I currently have.

Measurement – Is there any software, regardless of the operating system, able to measure the load impedance of an audio output?

I do not worry if it is inaccurate or could cause damage to the socket. I just want to know if this has already been done. There is online information on the use of an input as an oscilloscope, but I am trying to measure the load impedance of an output. Does anyone know if there is software that allows you to perform arbitrary measurements in ohmmeter on computer audio jacks?