VaptVupt Web — Post-Quantum Backup in Your Browser

Encrypt, compress, and protect files with quantum-resistant cryptography — from any browser.

One-command deploy. No accounts. No cloud. Your keys, your data, your server.

docker compose up -d
# → http://localhost:8181

This release bundles VaptVupt CLI 5.2.1 (with VaptVupt 2.65.3 codec and libvuptsdk 2.0.0). See CHANGELOG of bundled vaptvupt for the full list of changes.

Renamed from "Zupt-Web" together with the CLI's v3.0.0 rename, because of a prior INPI Brasil trademark registration on the name "Zupt" for unrelated software. The .zupt archive extension and container format (v1.6) are unchanged. One documented exception to cross-version compatibility: CLI v5.0.0 switched --pq/--pq-only to genuine FIPS 203 ML-KEM-768 (a breaking change), so hybrid/full-PQ encrypted archives and keys made by ≤ 4.2.1 — including all Zupt 2.x — cannot be decrypted by this release (and vice versa). Password-mode, --pq-sdk, and unencrypted archives are unaffected. The zupt command remains available inside the container as a symlink to vaptvupt, and the legacy ZUPT_* environment variables are still honored.

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What's new in 5.2.1

• Bundled CLI upgraded — Zupt 2.2.3 → VaptVupt 5.2.1: genuine FIPS 203 ML-KEM-768 (5.0.0), full post-quantum mode (4.2.0), source-only native build with vendored SDK (4.1.0), codec 2.48.2 → 2.65.3 with large ratio gains (5.1.0: level-9 text 3.77× → 5.98×, JSON 8.25× → 9.38×) and ~1.6–2× faster extreme-mode encode (5.2.0).
• Full post-quantum mode in the UI — new "Full-PQ Keypair" button and --pq-only public/private key fields in the compress/extract forms. ML-KEM-768 only, no classical X25519 layer.
• Archive header inspection — new Inspect card on the Verify tab (vaptvupt info): reports codec, encryption mode (password / hybrid PQ / full PQ / SDK v2), and block count without any credential. The same header detection the 5.2.1 GUI uses to auto-pick the right decrypt mode.
• Argon2id password KDF — the container builds the CLI WITH_SDK=1, so password-mode archives use Argon2id (RFC 9106) instead of PBKDF2.
• Renamed environment variables — VAPTVUPT_MAX_UPLOAD_MB, VAPTVUPT_KEY_TTL_SEC, VAPTVUPT_BIN, VAPTVUPT_WORKDIR, VAPTVUPT_SECRET_KEY, VAPTVUPT_COMPRESS_TIMEOUT, VAPTVUPT_EXTRACT_TIMEOUT. The legacy ZUPT_* names still work as fallbacks.
• Repo renamed — git.securityops.co/cristiancmoises/zupt-web → vaptvupt-web (mirrors on GitHub and Codeberg).

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Features

Feature	Description
SDK v2 key generation	HKDF + key commitment + HPKE binding + Argon2id. --pq-sdk workflow
Hybrid key generation	ML-KEM-768 + X25519. --pq workflow (FIPS 203 since v5.0.0 — keys/archives from ≤ 4.2.1 are incompatible)
Full-PQ key generation	ML-KEM-768 only, no classical layer. --pq-only workflow
Compress & encrypt	Upload files → .zupt archive. Password, --pq, --pq-only, or --pq-sdk (mutually exclusive)
Extract & decrypt	Upload .zupt + key/password → original files returned
Verify integrity	Validate every block's XXH64 + HMAC-SHA256 without extracting
Inspect header	Codec, encryption mode, block count — no credential required
Codec selection	AUTO (hardware-adaptive) · VaptVupt 2.65.3 (AVX2/NEON) · LZHP (universal) · Store
Block dedup	XXH64 fingerprint index, eliminates duplicate blocks before compression
Solid mode	Cross-file dictionary sharing for higher ratios on similar files
Levels 1–9	Fastest to maximum compression ratio

Security posture

• Runs as non-root in the container (vaptvupt, uid 1001) via USER vaptvupt in the Dockerfile. There is no root-owned process at runtime.
• no-new-privileges enabled in docker-compose.yml — no path to capability-based or setuid escalation.
• CSRF tokens on every form (double-submit cookie, hmac.compare_digest constant-time check).
• Rate limiting — 10 keygen/min, 30 compress·extract·test·info/min per IP.
• Tight Content-Security-Policy set by Flask in @app.after_request: default-src 'none'; script-src 'self' 'unsafe-inline'; …; frame-ancestors 'none' (the unsafe-inline is required because templates are deliberately single-file with inline <style> and minimal <script>; no separate .js/.css files are served).
• Full security header set applied by Flask: CSP, X-Frame-Options DENY, X-Content-Type-Options nosniff, X-XSS-Protection, Referrer-Policy, Cross-Origin-Opener-Policy, Cross-Origin-Resource-Policy, Permissions-Policy (camera/mic/geo/payment/USB/interest-cohort revoked).
• No shell=True — every subprocess call uses explicit argv.
• Path traversal protection — filenames sanitised, paths verified with Path.resolve().relative_to(WORKDIR).
• Password scrubbing — passwords are stripped from error output before being rendered to the browser.
• Keys auto-expire from the server after 4 h (VAPTVUPT_KEY_TTL_SEC env override).
• Workdir is a tmpfs (/tmp/vaptvupt-work, uid-mapped to 1001) — compress jobs never touch the container's writable layer.
• Container resource limits — memory: 4G in docker-compose.yml (defence against runaway compress jobs). CPU is uncapped by default; uncomment the cpus: line if your host is shared.
• HEALTHCHECK uses dedicated /healthz endpoint — no CLI fork on each probe, no rate-limit consumption, no auth roundtrip.
• Audited bundled CLI — VaptVupt 5.2.1 ships with make check 16/16, NIST/RFC KAT 16/16, ML-KEM-768 FIPS 203 conformance 3/3, plus the full security regression matrix (path traversal, block swap, dedup nonce, arg order, decode slack). See AUDIT.md.

Screenshots

Comparison

	VaptVupt Web	age + gzip	GPG + tar	Duplicati	BorgBackup
Post-quantum encryption	ML-KEM-768 hybrid and full PQ	—	—	—	—
SDK v2 (key commitment + HPKE binding)	✓ via --pq-sdk	—	—	—	—
Block-level dedup	XXH64 fingerprint index	—	—	—	HMAC
Web interface	Self-hosted Docker	CLI	CLI	Web	CLI
Zero deps in codec	Pure C11 (vaptvupt + VV codec)	Go	GnuPG	.NET	Python
Hardware-adaptive codec	AVX2/NEON auto	—	—	—	—
Per-block integrity	XXH64 + HMAC-SHA256 per block	—	Whole-file	—	HMAC
Docker one-command	docker compose up -d	—	—	Yes	—

Cryptographic stack

Algorithm	Standard	Purpose
ML-KEM-768	FIPS 203	Post-quantum key encapsulation (--pq hybrid, --pq-only pure)
X25519	RFC 7748	Elliptic curve Diffie–Hellman (hybrid layer)
AES-256-CTR	FIPS 197 / NIST SP 800-38A	Symmetric encryption (--pq, -p)
XChaCha20-Poly1305	RFC 8439 / draft-irtf-cfrg-xchacha	SDK v2 AEAD (--pq-sdk default)
AES-256-SIV	RFC 5297	SDK v2 nonce-misuse-resistant alternative
HMAC-SHA256	RFC 2104	Per-block authentication
HKDF-SHA3-256	RFC 5869 / FIPS 202	SDK v2 hybrid combiner
Argon2id	RFC 9106	Password key derivation (WITH_SDK build — this container)
PBKDF2-SHA256	RFC 8018	Password key derivation (source-only builds, 600 K iter)
SHA3 / SHAKE	FIPS 202	Hybrid key derivation, Keccak

Deploy

Prerequisites

• Docker and Docker Compose

Quick start

git clone https://git.securityops.co/cristiancmoises/vaptvupt-web && cd vaptvupt-web
docker compose up -d

Open http://localhost:8181.

Or grab the packaged release tarball (vaptvupt-web-5.2.1.tar.gz from the release page), verify it against SHA256SUMS, unpack, and run ./setup.sh — it checks Docker DNS, builds, starts, and verifies the stack in one go.

Tuning

# Cap upload size. Default: 2 GiB.
# Edit app.py — value in MEGABYTES:
app.config['MAX_CONTENT_LENGTH'] = 50 * 1024 * 1024   # 50 MB

# Or override at runtime via env (no rebuild needed):
docker run -e VAPTVUPT_MAX_UPLOAD_MB=50 -p 8181:8080 vaptvupt-web:5.2.1

# Tighten/relax key TTL on the server (defaults to 4 hours):
docker run -e VAPTVUPT_KEY_TTL_SEC=900 -p 8181:8080 vaptvupt-web:5.2.1

(The legacy ZUPT_* env names still work.)

Docker DNS fix

If the build fails with Temporary failure resolving 'archive.ubuntu.com':

echo '{"dns":["9.9.9.9","1.1.1.1"]}' | sudo tee /etc/docker/daemon.json
sudo systemctl restart docker

Or run ./setup.sh — it detects this case automatically.

Verify

curl localhost:8181/healthz   # {"ok": true, "service": "vaptvupt-web", "version": "5.2.1"}
curl localhost:8181/version   # {"version": "vaptvupt 5.2.1 ...", "ok": true}
docker exec -t vaptvupt-web vaptvupt version

Architecture

┌────────────────────────────────────────────────────┐
│  Browser  ──HTTP──▶  gunicorn  (port 8080, 2 wk) ──┐
│                                                    │
│                                              Flask app
│                                              (sets all
│                                               security
│                                               headers,
│                                               serves
│                                               /static/)
│                                                    │
│                                                    ▼
│                              /usr/local/bin/vaptvupt
│                                              │     │
│                                              ▼     │
│                              /usr/lib/vaptvupt/    │
│                              libvuptsdk.so.2       │
└────────────────────────────────────────────────────┘

• gunicorn binds 8080 directly as vaptvupt (uid 1001), 2 workers, 660 s worker timeout (deliberately above the app's 600 s CLI timeout so timeout errors render as pages), recycles workers every 1000 ± 100 requests. PID 1 is tini for proper signal forwarding and zombie reaping.
• Flask app (app.py) serves the UI, accepts uploads, sets all security headers in @app.after_request, serves static files from static/, and calls the vaptvupt CLI via explicit argv (no shell). Streams the result back to the browser.
• vaptvupt CLI (built from the bundled vaptvupt-5.2.1/ source tree, WITH_SDK=1) does the actual compress/encrypt/extract work. Links to libvuptsdk via RUNPATH=/usr/lib/vaptvupt. A legacy zupt symlink is kept for one major version cycle.

Project family

All maintained by Cristian Cezar Moisés on git.securityops.co:

• vaptvupt — CLI + GUI (this repo bundles a copy of its source)
• vaptvupt-web — this repo
• vaptvupt-codec — standalone LZ + tANS codec, embedded in vaptvupt
• libvuptsdk — C SDK powering --pq-sdk + Argon2id password KDF

Mirrors: GitHub · Codeberg

License

VaptVupt-Web is licensed under the GNU Affero General Public License v3.0 or later (AGPL-3.0-or-later).

The full license text is in LICENSE, preceded by a formal preamble explaining the rationale.

• You can run VaptVupt-Web freely — for personal use, internal company use, homelab self-hosting, research, or as a tool in your sysadmin workflow. The AGPL imposes essentially no obligations on simple use.
• If you operate a modified VaptVupt-Web as a hosted/SaaS service (a backup-management portal, a cloud archive viewer, a backup-as-a-service frontend, etc.), you MUST make the source code of your modifications available to the users of that service. This is the AGPL's "SaaS clause" and is the entire reason VaptVupt-Web is AGPL rather than GPL or MIT — VaptVupt-Web is by design a network-facing application, the exact deployment shape the AGPL exists to address.
• If you redistribute VaptVupt-Web (modified or not), the AGPL travels with it.

The bundled vaptvupt-5.2.1/ subdirectory contains the VaptVupt CLI source tree, also licensed under AGPL-3.0-or-later. The integrated VaptVupt 2.65.3 compression codec inside the bundled CLI is licensed under GPL-3.0-or-later (kept in sync with git.securityops.co/cristiancmoises/vaptvupt-codec). The vendored libvuptsdk.so.2.0.0 shared object is also AGPL-3.0-or-later. GPL-3.0-or-later is two-way compatible with AGPL-3.0-or-later via section 13 of both licenses.

Commercial licensing

If your intended use is incompatible with the AGPL — for example:

• Operating VaptVupt-Web as a hosted backup-as-a-service product without releasing your modifications
• Embedding VaptVupt-Web into a closed-source commercial portal or appliance
• Redistributing VaptVupt-Web as part of a proprietary product
• Requiring warranty, indemnification, or written terms

A commercial license is available. Contact: sac@securityops.co