Every password manager asks you to trust something. A hosted one asks you to trust its servers and whoever can reach them. Your browser's asks you to trust the browser. Obscura asks you to trust one file on your own disk — and then gives you the means to check that the file, and the program that opens it, are what they claim to be.
No account. No telemetry. No network code at all — not a disabled feature, but an application with no HTTP client in it.
Status: early releases, 0.1.x. Obscura has not been independently audited. Keep a second copy of anything you cannot afford to lose. What is being built next is listed under Roadmap.
Four ways in, and the vault tells you which of them travel with you.
The same vault from a terminal. obscura on its own opens a browsable view;
list, get and totp are there to be scripted.
- Argon2id, calibrated at vault creation against your actual hardware, so a fast machine buys you a slower attacker rather than a faster unlock
- XChaCha20-Poly1305 with a separate key per entry, derived via HKDF-SHA512
- Envelope encryption — one 32-byte vault key, wrapped once per unlock method. Changing your master password rewraps that key; it does not re-encrypt a single entry
- Hybrid X25519 + ML-KEM-768 key wrapping, so a vault copied today is not opened in fifteen years by a machine that breaks the classical half
- Four ways to unlock — master password, Windows Hello, a phone or tablet passkey, or a printed recovery code
- A master password that can be changed but never removed, and a recovery code that resets it when it is forgotten
- A master password policy that follows NIST SP 800-63B-4 — at least 15 characters, checked offline against about 29,000 common passwords, with no composition rules and no forced expiry
- Rollback detection — a keyed BLAKE3 watermark kept outside the vault and checked at every unlock, so a restored older copy is noticed rather than silently accepted
- TOTP codes, a password generator, CSV import from other managers, and encrypted export
- Auto-lock on idle, timed against both a monotonic and a wall clock, so a machine that slept through the timeout still locks
- Clipboard copies that clear themselves and opt out of Windows clipboard history and Linux clipboard managers
- A command line tool,
obscura, that browses or scripts the same vault
Installers are attached to each release.
| Platform | File |
|---|---|
| Windows | Obscura_0.1.1_x64-setup.exe |
| Windows, MSI | Obscura_0.1.1_x64_en-US.msi |
| Debian, Ubuntu | Obscura_0.1.1_amd64.deb |
| Fedora, RHEL | Obscura-0.1.1-1.x86_64.rpm |
| Any Linux | Obscura_0.1.1_amd64.AppImage |
The installers are not code signed, so SmartScreen shows "Windows protected your PC" the first time you run one. Choose More info, then Run anyway.
That warning is not a formality being skipped. A certificate that removes it costs 150 to 300 US dollars a year and requires a hardware token, extended validation certificates stopped bypassing SmartScreen in 2024, and Microsoft's free signing service is not offered to individuals outside the USA and Canada. So rather than buy the absence of a warning, Obscura publishes something you can check yourself.
Three checks, and the second is the one that matters.
The checksum tells you the file arrived intact. Every release includes a
SHA256SUMS file.
Get-FileHash .\Obscura_0.1.1_x64-setup.exe -Algorithm SHA256sha256sum -c SHA256SUMS --ignore-missingThe build provenance tells you where the file came from. Every installer carries a signed attestation, recorded in a public transparency log, naming the commit and the workflow run that produced it.
gh attestation verify Obscura_0.1.1_x64-setup.exe --repo DebanganMALI/ObscuraA checksum only proves the file matches a list published beside it, so anyone able to replace the installer could replace the list too. An attestation cannot be forged without push access to this repository, and the log is append-only and public. If you verify one thing, verify this.
The bill of materials tells you what went into it. Every release includes
Obscura_v0.1.1.cdx.json, a CycloneDX SBOM listing each of the crates compiled
into the application, with versions and licences, and it is attested against
the installers the same way.
gh attestation verify Obscura_0.1.1_x64-setup.exe --repo DebanganMALI/Obscura \
--predicate-type https://cyclonedx.org/bomOpen it, choose where the vault lives, set a master password. That is the whole setup — there is nothing to sign up for.
Add a recovery code before you add anything you care about. It is the only unlock method that survives losing both your memory and your machine, and Obscura will not let you remove your last portable one.
A stolen vault file is protected by the master password and Argon2id and nothing else, so Obscura is strict about the one and generous about the other.
| Rule | Why |
|---|---|
| At least 15 characters | Counted as characters, not bytes, so a Bengali or Hindi password is measured the same way as an English one |
| Not a common password | Compared against about 29,000 entries from the SecLists collections, ignoring case, spaces and hyphens, so Correct-Horse-Battery-Staple is caught too |
| Not a pattern | One short piece repeated, a handful of distinct characters, or a run along the alphabet or keyboard such as 1qaz2wsx3edc4rfv |
| Not the app's name | obscura does not count towards the fifteen characters |
| No composition rules | Four or five unrelated words beat a short string of symbols, and are far easier to remember |
The list ships inside the application, so checking a password never sends it anywhere. The strength meter asks the same Rust code that makes the final decision, so it cannot show green for a password that will then be refused, and it tells you which rule a password breaks while you type. A vault created before these rules still opens with its existing password.
The master password can be changed from Settings but never deleted, so a vault always has one. If you forget it, unlock with your recovery code: Settings then offers Reset master password, which sets a new one without asking for the old. The same rules apply to the new password.
Without a recovery code, a Windows Hello or passkey slot still opens the vault, but only a recovery code unlock can reset the password. With none of these, a forgotten master password ends the vault. There is no server holding a copy.
export OBSCURA_VAULT=~/.local/share/obscura/vault.obscura
obscura # browse the vault in the terminal
obscura list # titles and usernames, never a password
obscura list git # only matching entries
obscura get github # the password, to stdout
obscura totp github # the current code, to stdoutIn the browser: j/k to move, / to filter, p u t to copy the
password, username or code, r to reveal, ? for the keys, q to quit.
Three rules are built into all of it:
- The master password is never an argument. It is read from the terminal
without echo, or from stdin when stdin is not a terminal, so it never reaches
the process list or your shell history.
pass show master | obscura get githubworks. - Secrets go to stdout and everything else to stderr, so
obscura totp github | wl-copycopies six digits and nothing else — the banner, the countdown and the colour all go elsewhere. - An ambiguous query is an error, never a guess. If
get gitmatches two entries it lists them and exits non-zero. It will not pick one for you.
list, get and totp open the vault, do one thing and exit — no agent, no
cache, no socket. Browsing holds the vault open until you quit or it locks on
idle, and wipes the clipboard on the way out.
Your master password never encrypts anything directly. Argon2id turns it into a key that unwraps one 32-byte vault key, and every other unlock method unwraps that same key a different way. A recovery code is not a weaker back door; it opens exactly the same lock.
master password ──Argon2id(salt)──────> slot key ─┐
recovery code ──X25519 + ML-KEM-768 ──────────────┼──> VAULT KEY ──┬─> entry keys
passkey ──WebAuthn PRF(salt from vault id)────────┘ └─> watermark key
That indirection is why changing your master password is instant on a vault of any size, and why adding a passkey touches nothing but a single header field.
The vault file itself is one file: an eight-byte magic, a version, a plaintext CBOR header, and a sealed body. The header is deliberately not encrypted, because it is the body's additional authenticated data — edit any part of it and the body stops decrypting rather than decrypting into something else.
Being specific about what that leaks: without any credential, someone holding your vault file can read its id, its timestamps, its revision number, the Argon2id cost, and how many unlock methods it has, of what kind, with what labels. They cannot learn how many entries exist, how large any of them is, or anything about their contents.
docs/architecture.md has the byte layout, the full key hierarchy, the unlock and save sequences, and an annotated file tree.
Five library crates and two front ends. The cryptography does not know what a vault is, the vault does not know what an operating system is, and neither knows there is a user interface.
obscura-crypto Argon2id · XChaCha20-Poly1305 · HKDF-SHA512
keyed BLAKE3 · hybrid X25519 + ML-KEM-768
|
obscura-vault file format · entries · key slots · TOTP
recovery codes · generator · CSV import · export
|
+---------------------------+
| |
src-tauri + ui/ obscura-cli
Tauri commands, session list · get · totp · browse
watermark, clipboard banner, colour, ratatui
|
obscura-platform Windows Hello, file permissions
obscura-webauthn WebAuthn PRF for phone passkeys
obscura-platform and obscura-webauthn compile to stubs where the underlying
API does not exist, so the workspace builds on every target.
| Windows | 10 version 1809 or newer, x64 |
| Linux | any desktop with WebKitGTK 4.1 |
| Windows Hello | a machine with Hello already set up |
| Phone passkeys | Windows with WebAuthn API version 4 or newer, and a phone that supports passkeys |
| Terminal browser | any terminal; colour is skipped when NO_COLOR is set or output is piped |
The interface is four static files with no npm dependencies and a
default-src 'none' content security policy.
cargo build --workspace
cargo nextest run --workspace
node --test ui-tests/logic.test.js ui-tests/shell.test.jsThe interface tests use only Node's built-in test runner, so there is nothing to install for them beyond Node itself.
The desktop application needs the Tauri CLI:
cargo install tauri-cli --version "^2" --locked
cargo tauri build- Property tests over the cryptography, and RFC 6238 vectors for TOTP
- Five fuzz targets — the header decoder, whole-vault parsing, the portable export decoder, CSV import, and recovery code parsing
- Mutation testing. 544 mutants generated, 464 caught. Of the fifteen that survived, fourteen were proved equivalent by hand and the fifteenth is a real gap that safe Rust cannot express, documented rather than hidden
cargo denyfor licences and advisories,gitleaksfor secrets, and Dependabot on the lockfile- Clippy at
pedantic, withunwrap_usedandmem_forgetdenied outright - Interface tests on Node's built-in runner, with no npm packages: the interface's decisions - which unlock methods can be removed, what the editor sends to Rust, how a rollback is confirmed - plus guards that the page loads only its own scripts, the content security policy still denies by default, the code has no way to reach the network, and every command and element it names really exists
What the suite does not cover, and why, is in docs/testing.md and docs/mutation-testing.md. The short version: the interface's logic is tested, but how it paints the page is still checked by hand.
Planned for 0.2.0, roughly in this order:
- Refuse common, repetitive and sequential master passwords, with the strength meter computed in Rust
- Keep each vault's rollback watermark independent, so resetting one never weakens another
- Automated tests for the interface, using Node's built-in test runner and still no npm dependencies
- Tests for the terminal browser against ratatui's test backend
- Ship the
obscuracommand line tool as a release download - Run the application-level tests on Windows as well as Linux
- A password health view: reused, weak and old passwords, computed locally
- Lock secret memory pages with
VirtualLockandmlock, so keys cannot be written to swap - A written threat model, and a security posture document mapped to the ISO/IEC 27001:2022 Annex A controls that apply to a single application
Later: Unicode normalisation of master passwords, which needs a migration path so existing non-ASCII passwords keep working.
Report vulnerabilities as described in SECURITY.md.
Obscura collects nothing and makes no network requests. See docs/privacy-policy.md.
GPL-3.0-or-later. See LICENSE.
Built by Debangan Mali, who also wrote Salt-miner.