CVE-2026-33654: Nanobot AI Assistant Indirect Prompt Injection via Email Channel
Date: 2026-04-04
Tags: malicious-tool, malware
Executive Summary
An indirect prompt injection vulnerability in nanobot's email channel processing module allows remote, unauthenticated attackers to execute arbitrary LLM instructions and system tools without user interaction by sending malicious prompts via email, bypassing channel isolation in a stealthy zero-click attack (CVSS 8.9, HIGH severity).
Campaign Summary
| Field | Detail |
|---|---|
| Campaign / Malware | Nanobot Email Channel Exploitation |
| Attribution | Unknown (confidence: none) |
| Target | Nanobot AI assistant users |
| Vector | Email-based indirect prompt injection |
| Status | active |
| First Observed | 2026-03-23 |
Detailed Findings
Prior to version 0.1.6, the email channel processing module in nanobot (nanobot/channels/email.py) allows remote, unauthenticated attackers to execute arbitrary LLM instructions and subsequently system tools without any interaction from the bot owner. By sending an email containing malicious prompts to the bot's monitored email address, the bot automatically polls, ingests, and processes the email content as highly trusted input, fully bypassing channel isolation. Version 0.1.6 patches the issue. This represents a novel zero-click attack surface for personal AI assistants that monitor email channels, as the attacker requires no user action to trigger malicious behavior.
MITRE ATT&CK Mapping
| Technique | ID | Context |
|---|---|---|
| Prompt Injection | T1598 | Attacker injects malicious prompts via email to override agent behavior |
| Indirect Command Execution | T1203 | Email-triggered prompt injection leads to execution of arbitrary system tools |
IOCs
Domains
_GitHub advisory CVE-2026-33654; no IOCs published_
Full URL Paths
_GitHub advisory CVE-2026-33654; no IOCs published_
Splunk Format
_No IOCs available for Splunk query_
Package Indicators
nanobot < 0.1.6
Detection Recommendations
Monitor nanobot deployments running versions < 0.1.6; review email logs for suspicious prompts; implement input validation on email-sourced content before LLM processing; deploy prompt injection detection on email-triggered agent workflows; isolate nanobot instances from sensitive systems.
References
- [CVE Threat Intelligence] CVE-2026-33654: Nanobot indirect prompt injection via email (2026-03-27) — https://cve.threatint.eu/CVE/CVE-2026-33654