Friday, September 11, 2026

Pixel Perfect Browser Extension Exploited for Stealth Script Injection and Security Header Stripping

A popular Chrome add-on, “QuickLens – Search Screen with Google Lens,” has quietly morphed from a legitimate productivity tool into a full‑fledged remote code-execution platform that abuses browser trust, security headers, and silent auto‑updates.

What began as a simple Google Lens wrapper ended in a covert C2‑driven campaign capable of injecting arbitrary scripts into any site a victim visits.

Its early versions used a straightforward background service worker for window and capture management and a content script for UI overlays, with network calls limited to Google domains and no obfuscation or suspicious logic.

The extension’s wide but understandable permissions (activeTab, scripting, screen capture‑related access, and a content script injected on all pages) appeared normal for its functionality.

QuickLens originally provided on‑screen Google Lens search with features like screen capture, area selection, YouTube frame lookup, and Amazon product discovery, eventually reaching around 7,000 users and even earning a Featured badge in the Chrome Web Store.

QuickLens platform (Source : Annex).
QuickLens platform (Source : Annex).

The original developer identity, backed by multiple legitimate extensions, gave little indication that anything was wrong until ownership quietly changed and a monetized codebase turned into an attack platform overnight.​

Ownership Change and Malicious 5.8 Release

Just days after launch, QuickLens was listed for sale on ExtensionHub, a marketplace where developers sell extensions complete with users and reviews, a pattern now common in extension‑based supply chain attacks.

The Malicious Update (Source : Annex).
The Malicious Update (Source : Annex).

On February 1, 2026, control shifted to “LLC Quick Lens” under [email protected], with a new privacy policy on an almost non‑functional domain, signaling a likely throwaway entity.

On February 17, 2026, version 5.8 landed with a very different intent, adding declarativeNetRequestWithHostAccess and webRequest permissions, a new rules.json file, and a C2‑aware background.js that had never existed in the benign 5.7 build.

Google has since removed the extension from the store for a generic “policy violation,” but the underlying changes show a deliberate effort to bypass browser defenses and monetize access to users’ browsing sessions.

The newly introduced rules.json leverages Chrome’s declarativeNetRequest API to modify HTTP responses and remove key security headers from every page, frame, and XHR request.

The rule set strips Content-Security-Policy, CSP‑Report‑Only, X-Frame-Options, legacy CSP headers, and X-XSS-Protection, effectively eliminating browser‑enforced protections against inline script execution, clickjacking, and some reflected XSS defenses.

By globally clearing CSP, the attackers ensure that their later inline onload‑based payloads can execute even on well‑hardened sites that would normally block such constructs.

Combined with a content script injected everywhere, this gives the extension freedom to make cross‑origin requests and interact with page content in ways the original site owners never intended.

Pixel‑Based Script Injection

The updated background script introduces a C2 client talking to api.extensionanalyticspro.top, where the extension registers a persistent UUID, fingerprints the country via Cloudflare’s 1.1.1.1 trace endpoint, collects browser/OS data, and periodically polls /extensions/callback for instructions.

The developer, “[email protected]”, even has many other extensions published in his name (including a new, similar, recently published ‘Google Lens.

An Ordinary Extension (Source : Annex).
An Ordinary Extension (Source : Annex).

The server returns an array of JavaScript strings stored as cached-agents-data in local storage, with webRequest handlers monitoring a /finish endpoint to trigger on‑demand refreshes when the operator wants immediate changes.

Execution happens inside content.js using a clever pixel trick: for each payload string, the extension creates a hidden 1×1 GIF <img> element and assigns the C2‑provided JavaScript to the onload attribute before programmatically firing the load event.

When the image “loads,” the inline onload handler executes in the page context, allowing arbitrary script execution that can read session data, capture form inputs, scrape page content, and exfiltrate via the browser context itself.

For defenders, this highlights the need to treat browser extensions as part of the enterprise supply chain: monitor ownership changes, flag newly added network and declarativeNetRequest permissions, and use runtime behavior analysis to detect covert script injection patterns.

The QuickLens incident shows how a highly rated, Featured extension can become a browser‑resident C2 client with one update, turning 7,000 legitimate installs into an attack surface without any new downloads.

Because the actual malicious code is delivered at runtime from the C2 and never resides in the packaged source, static store reviews and basic permission monitoring are unlikely to see more than “image element helpers” and telemetry‑sounding names like extensionanalyticspro and safelyProcessElement.

Indicators of Compromise

TypeValue
Extension IDkdenlnncndfnhkognokgfpabgkgehodd
Extension NameQuickLens – Search Screen with Google Lens
C2 Domainapi.extensionanalyticspro[.]top
Developer Emailsupport@doodlebuggle[.]top
Privacy Policykowqlak[.]lat
Malicious Version5.8
SHA256fa3d0c8c8e9f3dacaa9f34e42ad63dceeba16689e055b90e9a903fa274d35df0

Follow us on Google NewsLinkedIn, and X to Get Instant Updates and Set GBH as a Preferred Source in Google.

Mayura Kathir
Mayura Kathirhttps://gbhackers.com/
Mayura Kathir is a cybersecurity reporter at GBHackers News, covering daily incidents including data breaches, malware attacks, cybercrime, vulnerabilities, zero-day exploits, and more.

Hot this week

How To Access Dark Web Anonymously and know its Secretive and Mysterious Activities

What is Deep Web The deep web, invisible web, or...

How to Build and Run a Security Operations Center (SOC Guide) – 2023

Today’s Cyber security operations center (CSOC) should have everything...

Russian Hackers Bypass EDR to Deliver a Weaponized TeamViewer Component

TeamViewer's popularity and remote access capabilities make it an...

Web Server Penetration Testing Checklist – 2026

Web server pentesting is performed under three significant categories: identity,...

ATM Penetration Testing – Advanced Testing Methods to Find The Vulnerabilities

ATM Penetration testing, Hackers have found different approaches to...

OpenMatter Network Realigns Leadership Team to Accelerate Global Commercial Growth

Melbourne, Florida, September 10th, 2026, CyberNewswire With its Verification Architecture...

Hackers Can Turn Vulnerable LiteLLM AI Gateways Into Root Access and Cloud Credential Theft

Nearly one in 10 internet-exposed LiteLLM AI gateways accepted...

Skullcandy Dime 3 Bluetooth Flaw Lets Nearby Attackers Hijack Audio and Microphone

Skullcandy Dime 3 wireless earbuds have a serious vulnerability...

Hackers Steal Active Directory Password Hashes Without Attacking Domain Controllers Directly

Threat actors are increasingly exploiting Active Directory replication mechanisms...

Fake GTA 6 Installer Steals Browser Passwords, Discord Tokens and Crypto Data From Gamers

Threat actors are exploiting anticipation around Grand Theft Auto...

Apple Xcode Integer Underflow Flaw Lets Crafted Archives Leak Memory and Crash Builds

A recently disclosed integer-underflow vulnerability in Apple’s modern Mach-O...

Palo Alto PAN-OS Buffer Overflow Lets Attackers Execute Arbitrary Code as Root

Palo Alto Networks has announced a high-severity buffer overflow...

New Phishing Attack Uses Blob URLs to Hide Malicious Pages From Security Scanners

A phishing campaign that moves the credential-harvesting page out...

Related Articles

Recent News