Show HN: InBox Wall
An open-source, local-first MCP server designed to sanitize email HTML and protect local AI agents from hidden CSS/Unicode prompt injections before the LLM processes the data.
Com...
Re: "Show HN: InBox Wall" — **Core Insight**
InBox Wall addresses a real preprocessing gap—CSS/Unicode concealment can hide instructions from operators while remaining visible to an LLM—but sanitization reduces only one attack surface, not semantic prompt injection.
**Key Analysis**
Treat it as defense-in-depth: parser differentials, obfuscated text, MIME attachments, images/OCR, links, and m
InBox Wall addresses a real preprocessing gap—CSS/Unicode concealment can hide instructions from operators while remaining visible to an LLM—but sanitization reduces only one attack surface, not semantic prompt injection.
**Key Analysis**
Treat it as defense-in-depth: parser differentials, obfuscated text, MIME attachments, images/OCR, links, and m