Patch Valve's CEG DRM for legally owned games to ensure long-term accessibility and preservation.

NoCEG is a toolkit designed to fully patch out Valve’s CEG (Custom Executable Generation) DRM from legally purchased Steam games. Its main purpose is digital preservation ensuring that games remain playable even after CEG servers are no longer available.

This repository includes three core tools required for resolving and patching CEG protection:

A command-line tool to scan the executable for CEG related functions and export the required information to noceg.json.

A dynamic library that uses the vectored exception handling to resolve CEG protected functions (both constant and stolen/masked ones) during runtime using the data from the previously generated noceg.json.

An utility that applies the final patch to a CEG protected executable.

Get the latest binaries from the Releases page.

Run the following command:

noceg_signatures.exe "Path\To\GameExecutable.exe"

Or simply drag and drop the executable onto noceg_signatures.exe.

• Rename the original steam_api.dll to steam_api_org.dll.
• Copy steam_api.dll from the NoCEG package into the game’s directory.
• Place the generated noceg.json file into the same folder.

Now, launch the game. A confirmation window should appear:

✅ "Successfully finished the task!"

The following titles require "ShouldRestart": true in noceg.json:

• Homefront
• The Darkness II
• Star Trek
• F.E.A.R. 3
• Risen 2

To enable this option, update your configuration from:

"ShouldRestart": false

to

"ShouldRestart": true

Some games (e.g. Duke Nukem: Forever) use integrity checks that can detect software breakpoints, which may lead to incorrect values. If this occurs, switch to hardware breakpoints by updating:

 "BreakpointType": 1

to

 "BreakpointType": 2

Drag the original executable onto noceg_patcher.exe.
A modified version will be generated with a suffix like _noceg.exe or _noceg.dll.

• Delete NoCEG’s steam_api.dll.
• Rename steam_api_org.dll back to steam_api.dll.

✔ 007™ Legends
✔ Aliens: Colonial Marines
✔ Aliens vs. Predator™
✔ Bionic Commando
✔ Call of Duty®: Black Ops
✔ Call of Duty®: Modern Warfare 2
✔ Call of Duty®: Modern Warfare 3
✔ Deadpool
✔ DeathSpank
✔ DeathSpank: Thongs Of Virtue
✔ Duke Nukem: Forever
✔ DiRT Showdown
✔ DiRT Showdown Demo
✔ F1 2012™
✔ F1 Race Stars
✔ F.E.A.R. 3
✔ GRID 2
✔ Homefront
✔ Homefront Demo
✔ Just Cause 2
✔ Just Cause 2 Demo
✔ Kane & Lynch 2: Dog Days
✔ Kane & Lynch 2: Dog Days Demo
✔ Lara Croft and the Guardian of Light
✔ Lara Croft and the Guardian of Light Demo
✔ Madballs in...Babo: Invasion
✔ Madballs in...Babo: Invasion Demo
✔ Mafia II
✔ Mafia II Demo
✔ Prototype 2
✔ Risen 2
✔ Risen 2 Demo
✔ Saints Row: The Third
✔ Saints Row IV Inauguration Station
✔ Sid Meier's Ace Patrol
✔ Sid Meier's Ace Patrol: Pacific Skies
✔ Sid Meier's Civilization V
✔ Sid Meier's Civilization V Demo
✔ Sniper Elite V2
✔ Sniper Elite Nazi Zombie Army
✔ Sniper Elite Nazi Zombie Army 2
✔ Spec Ops: The Line
✔ The Amazing Spider-Man
✔ The Bureau: XCOM Declassified
✔ The Darkness II
✔ The Darkness II Demo
✔ The Lord of the Rings: War in the North
✔ Viking: Battle for Asgard
✔ Warhammer 40,000: Space Marine
✔ Warhammer 40,000: Space Marine Demo
✔ XCOM: Enemy Unknown

These are using allocated buffers for CEG protected functions and are not supported at this point:

• ❌ F1 2013™ / F1 2014™
• ❌ Call of Duty®: Black Ops II
• ❌ Sid Meier's Civilization®: Beyond Earth™
• ❌ XCOM: Enemy Within

To compile this project from source, use Visual Studio 2022.

This project uses the following open-source libraries:

• nlohmann/json – JSON for Modern C++
• mem – Memory utility helpers
• zydis – Disassembler framework

• Preserve access to the games long after CEG DRM servers shut down.
• Designed exclusively for legally owned copies of games.
• Reverse-engineered with care for accuracy and modularity.

Check LICENSE.

⚠️ This tool is intended solely for educational and preservation purposes.
Please ensure compliance with local laws and terms of service.