How ElasticSearch Works (Basic Concepts)

Published on Author gryzli

I’m going to skip the intro about Elasticsearch and it’s primary application (which is for search) and will go straight to the point.  If you need some basic understanding of what is Elasticsearch and how to use it, I suggest you to start with the official documentation which is one of the best software documentations… Continue reading How ElasticSearch Works (Basic Concepts)

WordPress WP GDPR Compliance Privilege Escalation Exploit

Published on Author gryzli

Two days ago (on November 08 2018) nasty WP exploit has been identified inside the popular GDPR wordpress plugin , that leads to privilege escalation.  The plugin has more than 100 000 active installations.  All versions prior 1.4.3 (except 1.4.3) are vulnerable to the exploit.    What is the actual vulnerability ?  More information about… Continue reading WordPress WP GDPR Compliance Privilege Escalation Exploit

Decoding \x{ZZZZ} utf8 strings inside perl

Published on Author gryzli

We have some cPanel accounts with Cyrillic language set to default, which makes cPanel to return escaped utf8 messages while you operating with the API.  One of the example messages I was getting , looked like this : \x{437}\x{430}\x{43f}\x{438}\x{441} \x{437}\x{430} \x{434}\x{43e}\x{43c}\x{435}\x{439}\x{43d} \x{201c} some-user-domain.com \x{201d} \x{432}\x{435}\x{447}\x{435} \x{441}\x{44a}\x{449}\x{435} \x{441}\x{442}\x{432}\x{443}\x{432}\x{430}. which is not very eye-friendly.   Using simple… Continue reading Decoding \x{ZZZZ} utf8 strings inside perl

Kibana Installation Under Centos / RHEL

Published on Author gryzli

Kibana is part of the famous ELK stack (ElasticSearch , Logstash , Kibana) and is best used for Vizualization and Interaction with your ES cluster.   When installing Kibana, it is good to make sure that your Kibana version is coresponding to your ES version. For example if you have installed ES 6.X , it… Continue reading Kibana Installation Under Centos / RHEL

Elasticsearch Installation How-To (Centos 7)

Published on Author gryzli

Elasticsearch install is pretty straight forward (also making cluster of elastic nodes).The following howto is about installing elasticsearch 6.x, which is the current latest version. I’m not going to talk about the hardware requirements, because they strongly depend on the setup and the data that’s going to be inserted into the cluster.There is one thing,… Continue reading Elasticsearch Installation How-To (Centos 7)

Nginx 99: Cannot assign requested address to upstream

Published on Author gryzli

If you are using Nginx for reverse or caching proxy and you are making some good amount of traffic, soon or later you are going to have issues with the TCP connections between Nginx and your backend.  You will start getting error messages looking like this:  [crit] 2323#0: *535353 connect() to 127.0.0.1:8080 failed (99: Cannot… Continue reading Nginx 99: Cannot assign requested address to upstream