Matrix-style code representing data theft by browser extensions

Chrome Extensions Stealing Your Data: The 2026 Blacklist

Incogni's research reveals 52% of AI Chrome extensions collect user data. Grammarly and QuillBot ranked most privacy-damaging among popular tools. Two malicious extensions already stole ChatGPT conversations from 900,000 users.

LORIS.PRO Feb 12, 2026 4 min read

52% of AI-powered Chrome extensions collect user data, according to Incogni's 2026 analysis of 442 extensions. Grammarly and QuillBot are flagged as the most privacy-damaging popular tools—collecting keystrokes, website content, and personal communications. Two malicious extensions already compromised 900,000 users by stealing ChatGPT and DeepSeek conversations every 30 minutes. Check your extensions now: chrome://extensions.

The Numbers Are Alarming

Incogni analyzed 442 AI-powered Chrome extensions for their 2026 privacy report. The findings should concern anyone who uses browser extensions—which is most of us.

Over half of these extensions collect some form of user data. 29% collect personally identifiable information. And 42% request "scripting" permissions—allowing them to read everything you type and see every page you visit.

52% Collect User Data
900K Users Compromised
115.5M Downloads Affected

The Malicious Extensions (Remove Immediately)

Security researchers at OX Security discovered two Chrome extensions actively stealing ChatGPT and DeepSeek conversations. Combined, they compromised 900,000 users:

These extensions exfiltrated complete conversation histories to remote servers every 30 minutes. Despite containing data-stealing malware, one even received Google's "Featured" badge.

Source
"This data can be weaponized for corporate espionage, identity theft, targeted phishing campaigns, or sold on underground forums."
The Hacker News

Popular Extensions Flagged as High-Risk

Even legitimate, widely-used extensions pose privacy concerns. Incogni ranked Grammarly and QuillBot as "the most potentially privacy-damaging" among popular extensions (2M+ downloads).

Both collect:

The report notes both have "very low risk likelihood" of malicious use—but the data collection itself is extensive. Users must decide if the utility outweighs the privacy cost.

Highest-Risk Extension Categories

According to Incogni, these extension categories pose the greatest privacy risk:

How to Protect Yourself

Take these steps to audit your Chrome extensions:

FAQ

Which Chrome extensions are stealing data in 2026?
Two malicious extensions were caught stealing ChatGPT conversations from 900,000 users: "Chat GPT for Chrome with GPT-5, Claude Sonnet & DeepSeek AI" (600K) and "AI Sidebar with Deepseek, ChatGPT, Claude, and more" (300K). Grammarly and QuillBot were also flagged as high privacy risk.
Is Grammarly safe to use?
Incogni ranked Grammarly as one of the most privacy-damaging popular extensions due to extensive data collection. However, it has low risk likelihood of malicious use. Review the permissions and decide based on your privacy tolerance.
How can I check if a Chrome extension is safe?
Go to chrome://extensions, click "Details" on any extension, and review permissions. Be cautious of "scripting", "activeTab", or "all websites" access. Check reviews and developer reputation.