What is click injection?

Click injection is a sophisticated form of mobile ad fraud where a malicious app (on an Android device) listens for “install broadcasts” and then fires a fake ad click at precisely the right moment: just before another app finishes installing. This makes it appear as though the fraudster was responsible for the install, allowing them to take credit for attribution and claim cost per install (CPI) payouts.

Unlike traditional click spamming, click injection exploits a very narrow timing window and system-level signals (i.e. Android’s install broadcasts) to make fraudulent clicks seem legitimate. The attacker either owns or embeds code in an app installed on a user’s device, turning that app into a listening tool for opportunistic fraud.

This tactic is particularly damaging because it targets real users and real installs, but attributes them incorrectly.

Click injection relies on perfect timing and a compromised app already present on the user’s device. Here’s how the fraud typically plays out:

1. A user downloads a legitimate app.
2. A malicious app already on the device detects the install broadcast.
3. It immediately triggers a fake click to an ad network or mobile measurement partner (MMP).
4. The fraudster receives attribution credit for the install, despite contributing nothing to user acquisition (UA).

The entire process takes milliseconds. And because the click occurs just before install completion, the attribution window often validates it, unless robust fraud detection measures are in place.

Most obviously, fake ad engagements siphon off advertising budgets that could have been used to reach more users. But click injection doesn’t just waste budgets, it distorts attribution, skews performance data, and undermines the effectiveness of entire UA strategies.

At a financial level, fraud click injection siphons ad spend away from legitimate acquisition channels. CPI campaigns are particularly vulnerable, as payouts are triggered by installs, not by genuine user engagement. Every misattributed install means money spent on a user who was never influenced by the ad being credited.

But the impact goes beyond cost:

• Organic cannibalization: Click injection often intercepts organic installs, leading marketers to believe paid activity is driving more impact than it really is. As a result, organic performance is underreported and undervalued.
• Partner misalignment: Fraudsters can operate across affiliate, demand-side platform (DSP), or SDK-based traffic sources. When attribution is compromised, so is your ability to evaluate which partners are truly performing.
• Optimization misfires: Marketing teams rely on attribution data to adjust budgets, creative, and targeting strategies. If click injection is inflating results in certain channels, decisions based on that data are likely to underperform.

Left unchecked, click injection weakens confidence in attribution data and undermines the entire foundation of performance marketing.

The downstream effects can also show up in user LTV models. Fraudulently attributed installs may appear to underperform (because the user wasn’t actually acquired through the paid channel), skewing return on ad spend (ROAS) calculations and leading to inaccurate lifetime  value (LTV) forecasts.

In short, click injection doesn’t just inflate your CPI, it degrades your decision-making.

Click injection exploits a specific Android system feature: install broadcasts. These are signals sent when an app is installed, uninstalled, or updated—originally intended to help apps coordinate behavior on the same device. Fraudsters use them to detect exactly when a new app is being installed, allowing them to fire a fake ad click just before the process completes. This timing tricks attribution systems into crediting the install. 

While newer Android versions limit access to these signals, the behavior remains viable on older devices and continues to be used in mobile app fraud today.

Because click injection mimics real user behavior with precise timing, blocking it requires more than basic attribution filters. It calls for purpose-built, proactive fraud prevention that can detect abnormal patterns and reject fraudulent installs in real time. 

Adjust’s Fraud Prevention Suite includes a dedicated click injection filter designed to stop this form of attack before it affects reporting or spend. For teams running CPI campaigns at scale, it’s a critical layer of protection, not