Two rogue Chrome extensions have compromised over 900,000 users by secretly exfiltrating ChatGPT and DeepSeek conversations, along with full browsing histories, to attacker servers.

Discovered by OX Security researchers, the malware impersonates the legitimate AITOPIA AI sidebar tool, with one fake even earning Google’s “Featured” badge.

The OX Research team identified the threat during routine analysis, revealing extensions that clone AITOPIA’s interface for chatting with LLMs like GPT and Claude.

Named “Chat GPT for Chrome with GPT-5, Claude Sonnet & DeepSeek AI” (600K+ users, ID: fnmihdojmnkclgjpcoonokmkhjpjechg, version 1.9.6) and “AI Sidebar with Deepseek, ChatGPT, Claude and more” (300K+ users, ID: inhcgfpbfdjbjogdfjbclgolkmhnooop), they request “anonymous analytics” consent to mask data theft.

Threat actors host privacy policies on Lovable.dev to obscure origins, and uninstalled extensions redirect to the other.

How the Malware Operates

Installed extensions monitor tabs via chrome.tabs.onUpdated API, generating a unique “gptChatId” per victim. On detecting chatgpt.com or deepseek.com URLs, they scrape DOM elements for prompts, responses, and session IDs, storing data locally before Base64-encoding and sending batches to C2 servers like deepaichats.com or chatsaigpt.com every 30 minutes.

This captures proprietary code, business strategies, PII, search queries, and internal URLs missed by AITOPIA’s disclosed server storage.

Stolen chats risk exposing intellectual property, corporate secrets, and personal data for espionage or sale on dark web forums. Browsing logs reveals habits, tokens, and org structures, enabling phishing or identity theft across affected enterprises.

As of January 7, 2026, both extensions remain downloadable, with the first stripped of its “Featured” status post-disclosure but updated as recently as October 2025.

Users should visit chrome://extensions, remove by ID, or use store pages: ChatGPT extension, AI Sidebar. Avoid unverified extensions regardless of badges; stick to reputable sources.

IoCs

Type	Value	Notes
Extension name	Chat GPT for Chrome with GPT-5, Claude Sonnet & DeepSeek AI	Malicious AI sidebar-style extension
Extension ID	fnmihdojmnkclgjpcoonokmkhjpjechg	Chrome Web Store ID
Version	1.9.6	Reported malicious build
SHA-256 hash	98d1f151872c27d0abae3887f7d6cb6e4ce29e99ad827cb077e1232bc4a69c00	Package hash
Extension name	AI Sidebar with Deepseek, ChatGPT, Claude and more	Second malicious extension
Extension ID	inhcgfpbfdjbjogdfjbclgolkmhnooop	Chrome Web Store ID
Version	1.6.1	Reported malicious build
SHA-256 hash	20ba72e91d7685926c8c1c5b4646616fa9d769e32c1bc4e9f15dddaf3429cea7	Package hash

Network and C2 IoCs

Category	Domain / Endpoint	Notes
C2 endpoint	deepaichats[.]com	Receives stolen chat data and URLs
C2 endpoint	chatsaigpt[.]com	Additional C2 for exfiltrated data
Lovable-hosted server	chataigpt[.]pro	Used for privacy policy / infra hosting
Lovable-hosted server	chatgptsidebar[.]pro	Used for uninstall redirect and infra

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