Lykrin Security ResearchSource code review and security research for self-hosted software.https://lykrin.github.io/2026-09-30T00:00:00ZLykrinhttps://github.com/Lykrin SSH adapters and remote shell boundarieshttps://lykrin.github.io/research/vpn-remote-command-boundaries.html2026-09-30T00:00:00ZPython → SSH → container → sh -c: avoiding a local shell does not stop the remote shells parsing. Found unquoted inner-shell operands and a validator that accepts a trailing newline; proposes per-argument quoting and full-string matching. BDO Companion: pipe authorization, UIAccess, and signinghttps://lykrin.github.io/research/bdo-companion-0-7-3-security.html2026-09-30T00:00:00ZBDO Companion 0.7.3 (Windows): static review of the overlay's named-pipe security, its UIAccess manifest request, and embedded signing material versus verified trust. Nothing was executed. Glance configuration controls a privileged network clienthttps://lykrin.github.io/research/glance-request-destination-authority.html2026-09-30T00:00:00ZGlance v0.8.6 SSRF: response-supplied URLs and same-host redirects let widget requests reach other services and routes. A loopback Go probe shows both; fixed identifiers and route policy close them. Where Glance API strings acquire markup authorityhttps://lykrin.github.io/research/glance-active-content-boundary.html2026-09-30T00:00:00ZGlance v0.8.6 custom API widgets: nine experiments show where trusted-HTML and trusted-URL conversions turn API strings into active markup. Template diffs remove the unnecessary trust assertions. Closing an intake's outbound trust-boundary gaphttps://lykrin.github.io/research/support-intake-egress-isolation.html2026-09-26T00:00:00Znftables egress: a sandboxed intake guest with locked-down ingress could still open TCP connections to protected internal hosts. A default-drop output policy blocked them; health checks and proxy traffic kept working. Glance: TLS, redirects, and the browser boundaryhttps://lykrin.github.io/research/dashboard-credential-transport.html2026-09-26T00:00:00ZGlance v0.8.6: eight widget fetches had TLS certificate verification disabled. Removed all eight, then traced API credentials through redirects and templates with a loopback Go probe comparing Authorization and x-api-key handling. Authentik discovery is not a client's grant allowlisthttps://lykrin.github.io/research/authentik-grant-policy.html2026-09-26T00:00:00ZAuthentik 2026.8.3: OIDC discovery advertises a fixed grant list, but enforcement reads each provider's stored config. A disabled flow can still be listed, and a supported one can be missing. A backup contract failed safely while its health display stayed greenhttps://lykrin.github.io/research/backup-contract-observability.html2026-09-26T00:00:00ZInventory drift made a backup watchdog exit before checking capacity and sync freshness, while health stayed green. The encrypted copies existed; the detection path did not. Reconciliation restored monitoring. Encrypted backups need a key path that survives the outagehttps://lykrin.github.io/research/encrypted-recovery-bootstrap.html2026-09-26T00:00:00ZProxmox Backup Server client-side encryption: the documented protected key replica could not be retrieved. Recreated it, proved it matched the live key, and decrypted a real restore whose checksum matched the source. Native identity, local fallback, and narrow API exceptionshttps://lykrin.github.io/research/native-identity-and-api-exceptions.html2026-09-26T00:00:00ZPaperless-ngx and FreshRSS: native OIDC, local fallback login and API credentials are separate entry points. Disabling automatic social signup does not forbid social signup; API exceptions keep application authentication. Forgejo enrollment: OpenID is not OpenID Connecthttps://lykrin.github.io/research/forgejo-external-provisioning-policy.html2026-09-26T00:00:00ZForgejo v15.0.9: ENABLE_OPENID_SIGNUP governs legacy OpenID, not OIDC. Whether an external identity can create an account depends on separate OAuth2 settings, traced handler by handler. Hyprlock: separate authentication from reader cleanuphttps://lykrin.github.io/research/hyprlock-authentication-lifecycle.html2026-09-20T00:00:00ZHyprlock v0.9.6: blocking fprintd calls stalled the Wayland event loop, and a fingerprint unlock could log a failed PAM attempt. A local patch moves device work off the event loop without loosening authentication. A gateway restart without a general root-control APIhttps://lykrin.github.io/research/authenticated-ingress-and-fixed-control.html2026-09-06T00:00:00ZRust/Axum: a restart button without mounting the Docker socket. Proxy identity is trusted only from the real peer address, and a root helper exposes just status and restart for one fixed target, behind a lock and cooldown. A self-merge deleted the record it should preservehttps://lykrin.github.io/research/atomic-merge-integrity.html2026-09-05T00:00:00ZSQLite: merging a record into itself deleted it, and a late failure left half-copied associations. Identical IDs are now rejected at the API and store, and the whole merge runs in one transaction. Closing the direct-backend route around a login gatewayhttps://lykrin.github.io/research/proxy-backend-firewall-contracts.html2026-08-31T00:00:00ZForward auth only protects traffic that passes through the proxy. Source-specific nftables permits and drops close the direct route to backend listeners while keeping named health checks. Turning MQTT credentials into per-role topic boundarieshttps://lykrin.github.io/research/mqtt-topic-authorization.html2026-08-31T00:00:00ZShared MQTT broker: authentication alone did not limit which topics a client could use. A per-role ACL confines each client to its namespace; wildcard and integration exceptions are called out. Authorize the VPN target before invoking its backendhttps://lykrin.github.io/research/vpn-control-plane-authorization.html2026-07-05T00:00:00ZFlask VPN control plane: once backend names entered mutation URLs, authentication alone would let an isolated-plane user POST against the trusted plane. Per-plane membership checks now run before any privileged add or revoke. VPN revocation and rollback statehttps://lykrin.github.io/research/vpn-revoke-rollback-state.html2026-07-05T00:00:00ZWireGuard peer revocation touches four stores. Reconstructs a July fix and its ordering test, and shows how rolling back after a bookkeeping failure can restore a peer that was already revoked. Closing a failed transaction before the next caller uses ithttps://lykrin.github.io/research/rollback-after-partial-snapshot-write.html2026-07-02T00:00:00ZSQLite: a failed snapshot replacement left the shared connection mid-transaction, so the next caller's writes joined it. Explicit rollback before re-raising restores the old snapshot and a clean connection. Preserving manual ownership during an automatic rebuildhttps://lykrin.github.io/research/preserving-manual-lineage.html2026-06-21T00:00:00ZAn automatic rebuild kept user-edited groups but deleted their lineage edges. Cleanup now removes only edges it owns at both endpoints, and the regression test can no longer pass on empty output. Remove database-path authority from browser settingshttps://lykrin.github.io/research/database-configuration-boundaries.html2026-06-14T00:00:00ZFastAPI settings endpoint accepted db_path, so any API caller could choose the database location for the next start. Removed the field, rejected unknown fields, and moved the demo database out of a predictable shared temp path. Browser-origin checks across HTTP and WebSocket entry pointshttps://lykrin.github.io/research/browser-origin-and-websocket-boundaries.html2026-06-12T00:00:00ZCSRF and cross-site WebSocket hijacking on a local web app: Origin-versus-Host checks on every mutating route and the WebSocket handshake, with the remaining scheme and missing-Origin gaps documented.