Valve Anti-Cheat, otherwise known as VAC, is an anti-cheating system created by Valve and used mainly for multiplayer Steam games, released in 2002. It has stopped numerous amounts of players from cheating online. When a player is detected cheating in a VAC-Secure server, the player will be marked for cheating and will get banned from VAC servers permanently. VAC bans are delayed approximately 3-4 weeks.
With the first version of VAC, a ban took force almost instantly after being detected, and the cheater had to wait 2 years to have the account unbanned. Since VAC's second version, cheaters are not banned automatically. With the second version, Valve instituted a policy of 'delayed bans', the theory being that once a new hack is developed which circumvents the VAC system, it will spread amongst the 'cheating' community - by delaying the initial ban, Valve hopes to identify (and ban) as many cheaters as possible.
Like any software detection system, some cheats are not detected by VAC, and at times the only effective anti-cheat solution is a human administrator watching an online game. Some servers implement a vote system, in which case players can call for a vote to kick or ban the cheater.
VAC's success at identifying cheats and banning those who use them has also provided a boost in the purchasing of private cheats. These cheats are updated frequently to minimize the risk of detection, and are generally only available to a trusted list of recipients who collectively promise not to reveal the workaround.
Despite this, some servers implement a 'vote-kick' or 'vote-ban' system that allows players to vote to kick or ban alleged hackers which, to some players, is much more effective than the VAC program. Sometimes, this system is used to regularly check players and see if the others agree if someone is truly hacking. As such, this idea was implemented for Overwatch.
Currently, any player banned by VAC will be permanently unable to play in secured servers, with no way to become unbanned.
To obtain drops in Global Offensive, it is necessary to play in a server with VAC enabled. Drops are unavailable in servers that are not secured with VAC.
These hacks are usually either standalone or come bundled together as part of a multihack.
- A wallhack cheat allows the player to see through walls. These function by displaying objects that are normally obscured or replacing opaque game textures with semitransparent ones, allowing the hacker to see enemies before they would normally be in view. As the engine only renders the immediate area around the player, this does not allow a player to see the entire map at once.
- Speedhacks give the player increased speed, usually dramatically increased speed making it hard to target, hit, or even see the player. It works by sending false synchronization data to servers.
- The player appears to spin rapidly in all directions when moving, reducing the player's overall hit area and confusing the enemy. Also known as a spinbot.
- No recoil
- Reducing or removing the recoil keeps the player's gun shooting straight on the y axis without a kickback by removing gun physics.
- No spread
- Similar to a no recoil cheat, the no spread cheat makes the player's gun shoot straight along the x axis.
- Either through the use of scripting or prediction, aimbots help the player aim at enemies by moving the player's view to anticipate an enemy's position. They are usually programmed to aim specifically for the head.
- Auto Firing/Triggerbot
- Usually used in conjunction with an aimbot, auto firing automatically fires at enemies in the player's crosshairs.
- Silent Aim
- Similar to the aimbot and auto firing hacks, the silent aim hack allows a player to shoot at an enemy without having to actually aim at the enemy. From all points of view (player, world, or spectator), the player is not seen aiming at the enemy when the kill takes place.
- Barrel hack
- The barrel hack shows a line that depicts where the enemy is looking.
- Anti-flash and anti-smoke (also known as removals)
- Removal cheats disable or hide the flashbang and smoke grenade effect. This branched off the aforementioned wallhack.
- Although certain console commands can be activated for an entire server, bypassing allows the player to activate console commands normally restricted by sv_pure or sv_cheats.
- ESP (Extrasensory Perception)
- An ESP cheat shows textual information about the enemy, such as, health, name, and distance, and also information about weapons lying around the map, which could be missed without the hack. However, some legit server mods may actually make such information available to the player. The cheating occurs when the information is obtained where it would otherwise be hidden from the player.
- Upside-Down Hack
- This hack allows a player to flip the player's view upside down. It is often utilized to allow normal shots to the leg to be directed to the head of a target. However, the hack is very frustrating to use and is completely counterproductive due to the amount of difficulty it puts on aiming. Thus, the hack is often enabled along with an aimbot.
- Teleport Hack
- A cheater with this hack can choose where to (re)spawn in a map. It can be near enemies, hard to reach spots, or even outside the map boundaries. A player with aimbot and wallhack can eliminate targets without being easily spotted or shot at.
Some behavior exhibited during a game borders on cheating, is generally unfair, or can disrupt the game for the others playing, but is not considered cheating by VAC standards. Such behavior is independently policed by the server's administrators and will vary from server to server.
- Many players consider Ghosting a form of cheating. Ghosting is when a dead player who is spectating informs the player's live teammates of the enemies' movements, usually outside of the in-game voice chat. In a technical sense, ghosting is not a form of cheating as it does not modify any game files. Ghosting is not as prevalent in competitive mode, as dead players can only glimpse enemy movements for a few short seconds before being locked to spectating only other teammates, providing only minor information. Classic Casual does not allow dead players to chat (both voice chat and text chat) with alive players to prevent Ghosting. Users connected and spectating a match via GOTV are subject to a timed delay to disallow ghosting.
- Disruptive behavior/Griefing
- VAC will not ban players for disrupting online gameplay by team abusing, conflict with other players, spamming messages/voice chat, and other kinds of behavior that will annoy other players. VAC only bans players that uses the most recognized hacks. These actions are often countered with voting instead.
- A server with sv_cheats enabled
- VAC does not ban players who use sv_cheats since it is considered to be a built-in cheat and it can only be enabled by an admin. If enabled, all players have the ability to use cheats. VAC will only ban players who use third party cheats.
- VAC is not shared between GoldSrc and Source engines. For example, if a player is banned from GoldSrc servers, he or she can still play in Source servers.
To address the flaws that VAC had, Valve implemented a new program in Counter-Strike: Global Offensive called "Overwatch". Overwatch aids in identifying suspected cheaters by selecting the most trustworthy players, known as Investigators. Investigators are given a new menu item which presents the Investigator with the ability to watch demos of suspected cheaters or griefers, dubbed "The Suspect." The Investigator gets a limited version of the normal Spectator demo view, with the view being locked to the Suspect's player view and automatically skipping to the next round when the Suspect dies.
After watching 8 rounds of play, the Investigator decides whether the Suspect is guilty of the accused infraction. If the collective group of Investigators believe "The Suspect" to be guilty, he or she will be banned from Valve servers (permanently for cheating or a month for griefing). The Suspect demos available to Investigators are part of an automated process resulting from regular player reporting and test cases for the purpose of normalizing Investigator scores.
To protect player identities, all players, including "The Suspect", will have their names altered into generic names. Their avatars will be replaced with default T and CT icons. Chat and voice chat records are unavailable, and name tags for changed weapon names are not visible.
As of the June 10, 2015 update, players who participate in overwatch and submit enough reports also receive XP towards the player's profile rank. The player will be notified of the reward and receive the reward XP after completing a match on an official server.
Bugs & Exploits
- During watching a Overwatch case, opening "Inventory" causes all items' quality/rarity to change to "default".
- During watching a Overwatch case, sometimes Game UI (Health points, Armour, Ammo) can be hidden.
- The [ESC] key will not function.
- Holding Follow grenade key (default: Ctrl) then Suspect throw any grenade, cause "fast forwarding" overwatch case.
Behind the scenes
- File with overwach cases is named 'myassignedcase.evidence' and using unique extension
- Player can use
demouitool (or using combination:Shift+F2) to manipulate during case like "demo".
- Player can use
- Prior to the DreamHack 2014 tournament, Epsilon eSports and Titan were disqualified after members of each team were caught cheating by VAC.
- Valve Anti-Cheat on Wikipedia
- Valve Anti-Cheat on Steam Support
- Overwatch announcement on Counter-Strike.net