Diligence Rooms — Ed25519 deletion certificates, isolated viewer, watermarking
The Diligence Room becomes a cryptographically auditable record. Ed25519 JWS deletion certificates, a Guacamole-based isolated viewer for customer-uploaded documents, and two-stage watermarking (visible + steganographic) that identifies the external reader if a page turns up somewhere it shouldn't.
Diligence Rooms shipped a hardening pass this week that turns the room from an engagement-scoped workspace into a cryptographically auditable record: every artifact the room produces is now signed, every deletion is certificated, and the isolated viewer that lets external readers see the customer’s uploaded documents runs through a two-stage watermarking pipeline.
What’s in the release
- Ed25519 JWS deletion certificates.When a room closes, the platform issues a JSON Web Signature (RFC 7515 compact serialization) using an Ed25519 key. The certificate names the room, the engagement, the close timestamp, the artifacts purged, and the parties who can verify it. Anyone with the published public key can verify the certificate; the platform cannot fake or alter it after the fact. Replaces the earlier HMAC-SHA256 model.
- Certificate download endpoint.The vCISO Lite customer and every named external reader on a closed engagement can download the deletion certificate at any point after close. It’s a first-class artifact of the engagement, not a transient log entry.
- Isolated document viewer.Customer-uploaded documents now render inside a Guacamole-based isolated viewer that runs the render workload on the platform rather than shipping the document to the external reader’s browser. The document never leaves the room’s ephemeral GCS bucket. HTTP-tunneled for browser compatibility.
- Two-stage watermarking.Every page rendered through the viewer carries a per-reader watermark applied in two stages: at render time (visible watermark) and at pixel level (steganographic watermark). If a page is screenshot and shows up somewhere it shouldn’t, the watermark identifies which reader in which room saw it.
Why this matters
When a growing company hands sensitive cyber materials to an investor, an LP, or an acquirer’s deal team, the counterparty wants to read the material and the customer wants confidence that the material won’t leak elsewhere. The signed-artifact + isolated-viewer + watermark stack is what makes the customer comfortable enough to upload the material at all — and what gives the external reader a receipt they can defend to their own auditors or LPs later. Together with the February DD Room framework, this is the first version of the Diligence Room that’s actually enterprise-defensible.
Related reading
Autonomy You Can Audit: Signed Action Logs — the signed-substrate discipline the Diligence Room artifacts are built on.
The PE Buyer's Playbook for Cyber Due Diligence — the LOI-to-IC workflow the signed artifacts flow through.