Malicious Chrome Extensions Steal AI Chats & Data
Two popular ChatGPT and DeepSeek Chrome extensions with 900,000 installs secretly stole AI conversations and browsing data — straight from the official Chrome Web Store.
Yossi Pinhasov
YouCC Technologies
Malicious Chrome Extensions Are Stealing AI Chats and Sensitive Data
A fresh warning for anyone using AI helpers in the browser: two popular Chrome extensions for ChatGPT and DeepSeek, installed by roughly 900,000 users, were quietly exfiltrating AI conversations, browsing history and metadata to attacker-controlled servers — without users knowing. Yes, even the AI chats you assumed were "private."
What happened
The extensions were distributed through the official Chrome Web Store, carried high ratings, and presented themselves as convenient companions for ChatGPT and DeepSeek. In reality, they harvested the content of AI conversations along with browsing history and metadata, and sent it out to remote servers controlled by the attackers. The combined install base was around 900,000 users.
Why it matters
This is a pointed reminder that an extension's presence in an official store — or a high rating — is not proof that it is trustworthy, especially when AI is involved. Browser extensions run with broad access to page content, which makes them an ideal vantage point for stealing exactly the kind of sensitive prompts and responses people now share with AI tools. "Private" AI conversations are only as private as the extensions watching them.
What to do
- Audit installed browser extensions and remove any AI-related add-on you do not explicitly trust or need.
- Treat high ratings and official-store listings as necessary but not sufficient — review the publisher and requested permissions.
- In organizations, enforce an allowlist of approved extensions and block unmanaged installs, particularly for AI tooling.
- Assume anything pasted into a browser-based AI helper could be exposed, and keep sensitive data out of untrusted tools.
Read the original report for full technical details: The Hacker News coverage.
Shared from the CSC - Cloud Security Community community, by Yossi Pinhasov.
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