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Critical PHP Flaws: How to Update PHP 8.3, 8.4 and 8.5

Updated 22 October 2026. Commands below target Ubuntu/Debian package installations.

PHP has released emergency fixes for CVE-2026-109618 and CVE-2026-109619, both rated critical at CVSS 9.2. They can allow unauthenticated remote code execution. One involves unsafe out-of-memory cleanup; the other involves stale internal state across requests. Apache mod_php has a demonstrated attack before application code runs. PHP-FPM also requires patching. See the official announcement.

1. Check and update PHP

Back up your database, application files and configuration. Identify every runtime:

php -v
php --ini
dpkg -l 'php*' 'libapache2-mod-php*'

The CLI version may differ from the website. Check each virtual host, FPM pool, container and hosting panel.

Branch First fixed upstream version
PHP 8.3 8.3.36
PHP 8.4 8.4.27
PHP 8.5 8.5.12

Install these or later supported security releases. For PHP 8.3-FPM:

sudo apt update
apt-cache policy php8.3-common php8.3-fpm
sudo apt upgrade
sudo php-fpm8.3 -t
sudo systemctl restart php8.3-fpm

Substitute 8.4 or 8.5 for your installed branch. Review package upgrades, including extensions. If Apache uses mod_php:

sudo apache2ctl configtest
sudo systemctl restart apache2

Check vendor backports. Ubuntu fixes include 8.3.6-0ubuntu0.24.04.13 for 24.04 and 8.5.4-0ubuntu1.5 for 26.04. Compare complete revisions against Ubuntu’s security notice. Other repositories need their own advisories. An older-looking version can contain the fix.

Confirm the web runtime afterward and test login, uploads and database access. Updating WordPress or OJS alone does not update PHP.

2. Update containers separately

Host updates do not patch container PHP. Confirm a patched image exists, then replace app with your Compose service:

docker compose pull app
docker compose up -d --no-deps app
docker compose exec app php -v

Custom images require an updated base image and rebuild. Preserve persistent data. Shared-hosting users should request the exact patched revision.

3. Limit requests before PHP

In Nginx’s relevant server block:

client_max_body_size 8m;

Or inside the Apache virtual host:

LimitRequestBody 8388608

See the Nginx and Apache documentation. These impose an 8 MiB body limit. Adjust for legitimate uploads. In the active web runtime’s php.ini:

post_max_size = 8M
upload_max_filesize = 6M
max_file_uploads = 5
max_input_vars = 1000
max_input_nesting_level = 32
session.upload_progress.enabled = 0

Typical Ubuntu paths are /etc/php/8.3/fpm/php.ini for FPM and /etc/php/8.3/apache2/php.ini for mod_php. Adjust the branch number. php --ini reports CLI configuration only.

Test these example values. Disable file uploads if unused. Apply upload-progress settings at startup, then restart workers; application code and FPM .user.ini are too late for the confirmed early path.

Test Nginx with sudo nginx -t before reloading, or Apache with sudo apache2ctl configtest. These limits reduce exposure; they do not fix either CVE.

4. Emergency mitigation while patching

Prefer removing public PHP access and serving a static maintenance page. A PHP maintenance plugin still invokes PHP.

The OOM advisory recommends this incomplete emergency measure in the relevant FPM pool, such as /etc/php/8.3/fpm/pool.d/www.conf:

php_admin_value[memory_limit] = -1

This removes one controllable OOM trigger but permits unlimited per-request PHP memory, increasing denial-of-service risk. Use frontend limits and suitable cgroup/container boundaries. Underlying allocation failures remain dangerous; do not substitute RLIMIT_AS or RLIMIT_DATA. Audit overrides and restart all workers. Restore suitable finite PHP limits after patching.

For PHP 8.5, also set fatal_error_backtraces=0 in startup configuration. Remove invalid or obsolete per-request INI settings. These address specific stale-state paths only. Hiding warnings provides no protection.

5. Retire public PHP 7.4 applications

PHP 7.4 reached upstream end of life on 28 November 2022. Retire unused applications or migrate them to supported PHP. Legacy source patches and vendor fixes exist, but require explicit verification and should support temporary migration arrangements.

Remove forgotten subdomains, restrict administration through VPN/access policies, and keep FPM off public port 9000. Review logs, unexpected files, accounts and scheduled tasks. Patching does not remove existing backdoors. If compromise is suspected, isolate the system and preserve evidence. Follow NCSC guidance.

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How to Recover PDF Passwords with pdfcrack and NVIDIA-Accelerated Hashcat

Forgotten the password to an old PDF? You can try recovering it locally on Linux with pdfcrack.

This guide covers recovery of the password needed to open a PDF. Use it on your own files or files you have permission to recover.

 

IMPORTANT: pdfcrack runs on the CPU and has no built-in CUDA or NVIDIA GPU support. For NVIDIA acceleration, use Hashcat instead.

Start with a small password dictionary

A dictionary is a text file containing one password candidate per line. Start with a short list of passwords you remember using, then try common-password lists. This keeps the first attempt quick and helps check that the setup works before running a larger job.

Download the small SecLists file on Ubuntu:

wget -O common-passwords.txt 'https://raw.githubusercontent.com/danielmiessler/SecLists/master/Passwords/Common-Credentials/10k-most-common.txt'

You can also make a shorter first pass:

head -n 1000 common-passwords.txt > small.txt

This takes the first 1,000 lines. It does not guarantee that they are the best candidates. Extract compressed dictionaries before using them. A larger dictionary takes longer and still cannot recover a password that is absent from the list.

Recover a PDF password with pdfcrack

Install pdfcrack on Ubuntu:

sudo apt update
sudo apt install pdfcrack wget

Replace locked.pdf with your PDF filename:

pdfcrack -f locked.pdf -w small.txt

The -f option selects the PDF and -w selects the dictionary. User-password recovery is the default. If the first list fails, repeat with common-passwords.txt. See the pdfcrack manual for other options.

The project documents support for standard security-handler revisions 2, 3 and 4. Unsupported encryption requires another tool. Installing NVIDIA drivers will not add GPU support to pdfcrack.

Use Hashcat for NVIDIA acceleration

Install Hashcat and the supporting tools:

sudo apt install hashcat git python3
nvidia-smi
hashcat -I

You need a working NVIDIA driver and a compatible CUDA installation. The Hashcat requirements page lists the NVIDIA CUDA Toolkit requirement. Confirm that hashcat -I detects your NVIDIA GPU before continuing. A working nvidia-smi alone does not confirm that Hashcat can use it.

Hashcat needs an extracted password-verification record, rather than the PDF itself. The third-party pdf2hashcat script can prepare it locally:

git clone https://github.com/sighook/pdf2hashcat.git
python3 pdf2hashcat/pdf2hashcat.py locked.pdf > locked.hash
hashcat --identify locked.hash

Select the matching PDF mode using the identification output and Hashcat’s example hashes. The encryption settings determine the mode. The PDF filename or version alone is insufficient.

For example, only if mode 10500 matches your extracted record:

hashcat -m 10500 -a 0 locked.hash common-passwords.txt
hashcat -m 10500 locked.hash --show

Here, -a 0 selects a dictionary attack, while --show displays recovered results. Check the startup output to confirm that the NVIDIA device is being used. Mode 10500 is not suitable for every PDF.

Exhausted means the selected candidates were tried without a match. It does not mean the PDF has no password. GPU acceleration can increase guessing speed, but recovery time depends on the encryption and password. A long random password may remain impractical to recover.

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Revisiting Midnight Commander: A Classic Linux File Manager

Some Linux tools bring back memories as soon as you open them. Midnight Commander is one of those tools. Its familiar blue panels, text menus, and function keys recall the days when managing files in a terminal was an ordinary part of using a computer.

Known simply as mc, GNU Midnight Commander is a terminal file manager with two directory panels. Open your source folder on one side and the destination on the other, then browse and copy files using the keyboard.

Midnight Commander showing two directory panels and a function key menu in the terminal
Midnight Commander’s familiar two-panel interface. Screenshot from the official Midnight Commander project website.

The appeal of those blue panels

For anyone who remembers DOS-era file managers, this layout feels familiar. The available actions appear along the bottom of the screen, and the keyboard does most of the work. There is something satisfying about seeing both folders at once and moving through them without repeatedly typing ls and cd.

Midnight Commander also remains useful when working on a Linux server through SSH. It runs inside the terminal, so you can browse directories, inspect files, and organise folders without opening a graphical desktop. It includes a file viewer and an editor, too.

How to install Midnight Commander on Ubuntu

Install it using Ubuntu’s package manager:

sudo apt update
sudo apt install mc

Then launch it:

mc

Start with these shortcuts, documented in the official manual:

Key Action
Tab Switch between panels
F1 Open help
F3 View a file
F4 Edit a file
F5 Copy files
F6 Move or rename files
F7 Create a directory
F8 Delete files
F10 Quit

Modern desktops have changed how we manage files, but this old style still has its appeal. Two panels, clear actions, and a keyboard within reach are enough to make routine file management comfortable. If you have not used Midnight Commander for years, try typing mc again.

References

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Remembering WGAfakap.exe, a Windows XP Genuine Advantage removal tool – It’s already 20 years!

Twenty years ago I wrote WGAfakap.exe, a simple windows application that removes the Windows XP Genuine Advantage Tattoo.

WGAfakap was widely used around the world to help individuals or companies who has purchased a legitimate Windows XP from being nagged by the notorious “You May Be A Victim Of Software Counterfeiting, Solve It Now! ” screen.

I used Microsoft Visual Studio 6 and libctiny and wcrt library to keep WGAfakap small. And the result was a very small (less than 8kb of executable!) https://blog.mypapit.net/2006/05/solution-to-libctiny-and-wcrt-lnk2001-unresolved-external-symbol-__chkstk.html

I was obsessed with optimization and efficiency because I was poor back then. Couldn’t afford a decent computer with a lot of storage space and speed. Thus, efficiency was everything to me.

Although there are attempts to supress it, WGAfakap was famous and it was distributed through message boards and was being used across the world.

With careful searching, archived message board threads explaining how to use WGAfakap can still be found. The most recent of these discussions date to 2010, four years after its initial development

Most WGAfakap users probably almost reached 40 years old now. Give a shout out if you’ve heard or ever used WGAfakap!

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LobiShell: SSH Access to Linux Servers from Android

LobiShell saved SSH connections screen

Sometimes I need to check a Linux server when I’m away from my laptop. For small jobs, an Android SSH client is enough. LobiShell, developed by Lobianco Home Lab, is one option worth looking at.

It runs SSH sessions from an Android phone and also supports Mosh, SCP file transfers, port forwarding and SSH key management. These are useful features when you manage more than one Linux machine.

Advantages: LobiShell supports putty based private key format.

Connecting to your servers

LobiShell lets you save server connections and manage identities. A typical SSH connection needs the server address, SSH port, username and a password or private key. Once connected, you can use the terminal for commands such as:

uptime
free -h
df -h
docker ps
systemctl status nginx

The saved connections screen makes it easier to move between several machines without re-entering their details.

LobiShell connection manager, showing saved hosts and identities.
LobiShell connection manager, showing saved hosts and identities.

Finding devices on your network

LobiShell includes a network scanner that can help find devices on a local network. This is handy when you have several servers, small PCs or other machines in a homelab. You should still verify the host’s SSH fingerprint before trusting a new connection.

LobiShell local network scan and discovered devices.
LobiShell local network scan and discovered devices.

SSH, Mosh and file transfers

Regular SSH works well on a stable connection. LobiShell also supports Mosh, which is designed to cope better with intermittent connections and network changes. Mosh requires server-side setup, so it is not a drop-in replacement on every host.

SCP support lets you upload or download files, while SSH port forwarding can provide access to an internal service through an encrypted connection. For example, that can be useful when a web interface is restricted to the server’s private network.

Authentication and saved commands

The Identity Store manages SSH keys and passwords. LobiShell also advertises FIDO2 authentication with compatible hardware security keys. It has command snippets, too, so commands you frequently run can be saved instead of typed each time.

For sensitive servers, I would still use key-based login, verify host keys, and avoid exposing SSH directly to the public internet when a VPN is available.

Terminal appearance and backups

There are settings for colours, fonts and interface layout. That matters more than it sounds on a small touchscreen, especially when you have to read logs or work in a terminal for a while.

LobiShell app colour and theme settings.
LobiShell app colour and theme settings.
LobiShell terminal appearance and interface options.
LobiShell terminal appearance and interface options.

For moving settings between devices, LobiShell supports WebDAV synchronization, including compatible services such as Nextcloud. It also supports local peer-to-peer synchronization and exportable backups, with optional AES-256-GCM encryption.

LobiShell as SSH Client

If you only open an SSH terminal once in a while, a simple client may be sufficient. LobiShell becomes more interesting if you manage several servers and want saved identities, snippets, file transfers and synchronization in the same app.

The limitations are mostly those of working on a phone. Long commands and detailed configuration work are still easier with a keyboard and larger screen. But for checking a service, reading logs or restarting a container, it is a practical tool to keep installed.

Download: LobiShell on Google Play.

App details and screenshots: Google Play listing by Lobianco Home Lab. Features may change with future releases.

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A Guide to Melty: Game Mashups and AI Mod Creation

Official Melty SkyCraft screenshot showing a Minecraft-style player in Skyrim

Ever wondered what Minecraft would look like inside Skyrim? Melty offers game mashups that combine elements from games you already own.

One example is SkyCraft, where you explore Skyrim as a Minecraft player. Another is Elden Craft, which brings Minecraft elements into Elden Ring.

Official Melty SkyCraft screenshot showing a Minecraft-style player in Skyrim
SkyCraft. Screenshot from Melty’s official website.

Melty is currently free for Windows. Choose a mashup and press Play. According to its website, the app downloads the mod, handles the required setup and starts the game. Multiplayer mashups also provide invite links for friends.

Official Melty Elden Craft screenshot combining Minecraft elements with Elden Ring
Elden Craft. Screenshot from Melty’s official website.

The AI part comes into creating your own mashup. Melty provides instructions for coding agents such as Claude Code or Codex. You describe your idea, and the agent works on building and publishing it.

You still need to own the required games. This looks interesting for players who enjoy experimenting with mods and unusual game combinations.

Download Melty or visit melty.gg to learn more.