A regular expression is a set of characters, a string of characters if you will, that specify a pattern. Ever used the grep command? It makes use of them. The ‘grep’ command is very handful when one needs to look for certain things inside a text file, or looking for some specific pattern from another […]

A brief introduction to Regular Expressions

The LAMP stack (Debian 9)
LAMP stack stands for a software stack composed by Linux, Apache, MySQL and PHP (or Perl). It is used for many purposes and its common ground for system administrators. Since there are several of Linux distributions there are some differences in the way the LAMP stack is installed. In this guide we are using the […]

How to patch Spectre and Meltdown the ROM way
In a previous article I briefly, sort of, talked about the Spectre and Meltdown vulnerabilities. I have also written two guides to patch them from the OS side using a UNIX flavour from the BSD camp and a GNU/Linux distribution. Both actions resulted successful but there is a third way to patch this vulnerabilities. Regular […]

How to mitigate/solve the MDS vulnerabilities of Intel processors in FreeBSD
It had to happen again. Anyone betting on new hardware vulnerabilities on Intel processors would have won. This time these are called the MDS vulnerabilities, which stands for Microarchitectural Data Sampling. The trouble is the ones who would have really made big money would have been those stating the new CPUs were on the same […]

How to update FreeBSD using beadm
Beadm is a tool which provides a wonderful and distinctive functionality on Solaris, OpenIndiana and FreeBSD. It relies on the ZFS filesystem allowing to take a filesystem snapshot. That can be used to manage the so called boot environments which provide a great way to secure updates, even when everything goes down the tubes. Hence […]

How to analyze suspicious email
Millions of emails are sent and received every day. Most of them are just junk. And many among those are potentially harmful. Phishing still is one of the most effective ways for malicious actors to penetrate into well secured networks. The weakest link, too often, is the human factor. Training can help mitigate this 24×7 […]

A word on Spectre and Meltdown
As professionals and many aficionados know, early this year some widespread vulnerabilities were found on Intel CPU’s as well as on AMD’s. It was a bit later discovered the flaws also affected some RISC architectures such as Power and ARM. Everybody went nuts and the world seemed to be tumbling because of two CPU vulnerabilities […]

Microsoft’s Patch Tuesday – April 2020
For the first time here at adminbyaccident.com I will share some information about Windows patching that I hope can shed some light and help people on deciding what to patch and how quickly to patch. Digesting Microsoft’s Patch Tuesday releases is always tricky. The amount of information is overwhelming and since almost every company on […]

How to enable TLS traffic from the origin server on Cloudflare Argo Tunnel
As it can be read in the last post, setting up a Cloudflare Argo Tunnel to serve web content from home or corporate network without poking holes to it, is quite easy to achieve. In this article I’ll show you how to enable TLS traffic from the origin server on Cloudflare Argo Tunnel. Obviously, you […]

Reasonable amount of enabled modules on Apache HTTP
CentOS Ubuntu FreeBSD core_module (static) core_module (static) core_module (static) so_module (static) so_module (static) so_module (static) http_module (static) watchdog_module (static) http_module (static) access_compat_module (shared) http_module (static) mpm_prefork_module (shared) actions_module (shared) log_config_module (static) authn_file_module (shared) alias_module (shared) logio_module (static) authn_core_module (shared) allowmethods_module (shared) version_module (static) authz_host_module (shared) auth_basic_module (shared) unixd_module (static) authz_groupfile_module (shared) auth_digest_module (shared) access_compat_module (shared) […]
