A serious new class of Android attacks called Pixnapping lets any installed app (even one that asks for no permissions) snoop on what other apps display, everything from Gmail previews to Google Maps Timeline to one-time 2FA codes, by abusing Android’s rendering APIs and a hardware side channel. The research team that found the flaw demonstrated full end-to-end recoveries on multiple Google Pixels and a Samsung Galaxy S25, and they even show an optimized version that can nick Google Authenticator codes in under 30 seconds.
Think of Pixnapping as a clever, low-level screenshot trick that doesn’t use screenshots. A malicious app uses Android intents to force the target app’s pixels into the system’s rendering pipeline, overlays a stack of semi-transparent activities that perform carefully tuned blur and encode steps, then measures tiny timing differences caused by GPU compression (the “GPU.zip” side channel). Those timing differences reveal whether targeted pixels are white, black, or a particular color; repeating the trick and doing a little OCR-style math recovers text, including ephemeral 2FA codes. The paper explains the three-step pipeline: submit victim pixels, compute/enlarge them via blur hacks, then leak the result via timing.
The team instantiated Pixnapping on Pixel 6, 7, 8, and 9 devices and a Samsung Galaxy S25, showing it works across multiple hardware and graphics stacks. On Pixel phones, they traced the root cause to GPU graphical data compression behavior; on the Samsung device, the technique needed different tweaks, but it still worked. That means this is not a niche browser bug. It’s a platform-level attack with real consequences for apps that show sensitive info on the screen.
According to the researchers, they responsibly disclosed Pixnapping to Google back in February 2025. Google assigned CVE-2025-48561 and rated the issue High; a patch was released in September, but the team found a workaround and continued coordinating with Google and Samsung through October. Importantly, Google has told The Register that an additional fix targeting remaining attack vectors will arrive with the December Android security bulletin, so patched builds are on the way.
Should you panic? Not yet. Pixnapping requires the attacker to convince you to install and run an app that hides its malicious payload in plain sight, so basic app hygiene matters more than ever: avoid unknown APKs, scrutinize app sources, and prefer Play Store installs from reputable developers. The research team also notes that installing security updates as soon as your phone gets them is the best practical defense; Google’s December patch should materially reduce risk for patched devices.
Right now, the researchers don’t have a silver-bullet mitigation app that developers can drop in because the attack leverages fundamental Android layering and rendering behaviors. The paper urges platform fixes (restricting attacker measurement capabilities and letting sensitive apps opt out of third-party compositing) and calls on GPU vendors to address compression side-channels, though as of October, no GPU vendor has committed to a hardware fix.
If you’re a Pixel user: breathe, patch, and be picky. The tech here is neat (if you’re a security nerd) and scary (if you’re human), but Google’s commitment to another patch in December shows real progress. Until then: don’t sideload mystery apps, keep your phone up to date, and maybe don’t display your Authenticator codes while lunching in a café full of strangers.
For the Pixel crowd: we’ll keep an eye on the December bulletin and the team’s promised public artifacts and PoC (they say they’ll release code once patches are out). In short, Pixnapping is clever, powerful, and fixable. Update when the fix arrives, and your Pixel should be fine.
