Macetes TI

Block scraper bots nginx

For those not using wordpress at all and just want to block annoying scraper bots:

location ~* /wp- {
    deny all;
}

or better yet:

location ~* /wp- {
    return 302 https://www.youtube.com/watch?v=dQw4w9WgXcQ;
}

source:https://gist.github.com/nfsarmento/57db5abba08b315b67f174cd178bea88

Blocking access by user agent in Nginx

How to block access by user agent in Nginx. In this configuration, i will use ngx_http_map_module.

Inside http section:

include /etc/nginx/blacklist;

Inside server section (virtual host). We will return 444 status code.

if ($block_ua) {
        return 444;
}

The blacklist file (example)

map $http_user_agent $block_ua {
        default           0;
        ~*profound        1;
        ~*scrapyproject   1;
        ~*netcrawler      1;
        ~*nmap            1;
	~*sqlmap	  1;
	~*slowhttptest	  1;
	~*nikto		  1;
	~*jersey	  1;
	~*brandwatch	  1;
	~*magpie-crawler  1;
	~*mechanize	  1;
	~*python-requests 1;
	~*redback	  1;
}

For testing:

aelius@macbook:~$ curl --head -A "profound" https://www.unixteacher.org/
curl: (52) Empty reply from server

What is http status 444 ?

A non-standard status code used to instruct nginx to close the connection without sending a response to the client, most commonly used to deny malicious or malformed requests.

Harden bash_history and bash configuration files

Harden bash_history and bash configuration files by making them append-only:

chattr +a /home/user/.bash_history
chattr +a /home/user/.bash_profile
chattr +a /home/user/.bash_login
chattr +a /home/user/.profile
chattr +a /home/user/.bash_logout
chattr +a /home/user/.bashrc

Harden env variables by adding the following lines to /home/user/.bashrc:

shopt -s histappend
readonly PROMPT_COMMAND="history -a"
readonly HISTFILE
readonly HISTFILESIZE
readonly HISTSIZE
readonly HISTCMD
readonly HISTCONTROL
readonly HISTIGNORE

histappend tells bash to append the last $HISTSIZE lines to the $HISTFILE file when an interactive shell exits. PROMPT_COMMAND executes the given command prior to issuing each prompt. history -a appends the command typed just before the current one to $HISTFILE.

Disable access to other shells:

chmod 750 csh
chmod 750 tcsh
chmod 750 ksh

Tomcat as non root user

run

setcap cap_net_bind_service+ep /path/to/bin/java

ex: setcap cap_net_bind_service+ep /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java

Reconnect Wazuh agent

Add the manager's ip address in the configuration file /var/ossec/etc/ossec.conf <address>MANAGER_IP</address>
Register the agent in the manager. The simplest method is /var/ossec/bin/agent-auth -m MANAGER_IP
Restart the wazuh agent systemctl restart wazuh-agent.

Delete DFSR replication folders

md d:\emptyfolder

Robocopy.exe d:\emptyfolder "D:\System Volume Information\dfsr\Private" /purge

rd d:\emptyfolder

I found that at:

https://superuser.com/questions/78434/how-to-delete-directories-with-path-names-too-long-for-normal-delete

Enable ‘Minimize on Click’ on Ubuntu Quickly

Just open a Terminal window and copy/paste the following command:

gsettings set org.gnome.shell.extensions.dash-to-dock click-action 'minimize'

Hit enter for the change to take effect instantly.

If you don’t want to lose the ‘window’ picker (option 5 in the list above) run this command instead, which will introduce minimise on click but show the window picker if more than one window of a given app is open:

gsettings set org.gnome.shell.extensions.dash-to-dock click-action 'minimize-or-previews'

To undo the change (i.e. revert back to the default settings for the Ubuntu Dock) copy/paste this command:

gsettings reset org.gnome.shell.extensions.dash-to-dock click-action