* fix(email): guard user-supplied IMAP/SMTP hosts against SSRF
POST /api/email/accounts/test opened raw imaplib/smtplib connections to
whatever host:port the request body named, and POST/PUT /api/email/accounts
and PUT /api/email/config persisted arbitrary hosts for the background
pollers to contact. All of these sit behind require_user/require_owner with
no admin gate, so any authenticated user could make the server connect to
loopback, LAN and cloud-metadata targets (169.254.169.254) and read the
first 200 characters of the remote banner back out of the friendly error.
THREAT_MODEL.md lists email as admin-only; the tool layer honours that but
the HTTP routes did not.
Add check_outbound_host() to src/url_safety.py, a bare-host companion to
check_outbound_url() with the same classification (link-local, multicast,
reserved and unspecified always rejected; private/loopback only with
block_private) plus localhost-name handling and an explicit policy for names
that do not resolve. Wire it into the four email routes via
_check_mail_host(): non-admin owners (and everyone when
EMAIL_BLOCK_PRIVATE_IPS=true) also lose private/loopback targets, admins
keep the local-first LAN/Dovecot setups. Unresolvable names pass through
because the connect that follows fails with the same DNS error.
Regression tests cover the helper's policy table and each route: the test
route rejects before any socket opens, save routes reject before touching
the DB, admins keep loopback unless locked down, and an update that fails
validation leaves the stored row untouched.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TwcwfY2uQMxNRsK3y6xBAp
* fix(email): harden IMAP/SMTP SSRF protection against rebinding, TOCTOU, and unvetted hosts
- P0: Implement safe_create_connection() in src/url_safety.py to resolve hostnames once, validate every returned address against SSRF policy, and connect directly to the pinned IP. This eliminates DNS rebinding and TOCTOU while preserving TLS SNI and certificate hostname verification across IMAP, IMAPS, STARTTLS, SMTP, and SMTP_SSL.
- P1: Ensure unresolvable or deferred hostnames cannot become an unrestricted future connection capability by enforcing runtime SSRF validation fail-closed on every connection, while maintaining compatibility with offline configurations.
- P2: Extend SSRF enforcement to the core connection layer (_open_imap_connection, _send_smtp_message, _imap_connect) using ContextVar owner scoping, protecting pre-existing DB rows, restored configs, background pollers, and scheduled operations.
- P3: Allow admin and single-user access to IPv6 loopback (::1, [::1]) for local mail servers (e.g. Dovecot) by checking loopback before is_reserved, while keeping link-local, cloud metadata (169.254.169.254, 100.100.100.200), and non-admin restrictions strictly enforced.
- Add comprehensive regression and adversarial test coverage in tests/test_email_account_host_ssrf.py.
* fix(email): reject unresolved saved hosts without stdlib monkeypatches
Use the existing explicit policy IMAP/SMTP classes and canonical connect_outbound_tcp helper. Remove process-wide stdlib assignments, context-variable plumbing, redundant aliases and resolver-signature retries. Reject unsafe or unresolved hosts before account/config persistence, keep DNS work off the event loop, return fixed client errors, identify Alibaba metadata accurately and reject invalid TCP ports. Validation: 654 relevant email, URL-safety and CodeQL regression tests passed, 3 skipped. Three unrelated browser checks were excluded after environment failures (missing Playwright browser and Chromium timeout). Running-app checks verified rejected create/update/config requests leave stored data unchanged, administrator LAN configuration still works, and metadata/non-admin loopback are blocked.
---------
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
Co-authored-by: PR #6029 Reviewer <reviewer@odysseus-review.local>
Co-authored-by: Afonso Junior <chatgpt@yack.com.br>
The R09 scholarly hardening routes every hop through check_outbound_url with
block_private=True. On a DNS64/NAT64 network, an IPv4-only host can resolve
through the RFC 6052 Well-Known Prefix. For example, export.arxiv.org resolved
to 64:ff9b::924b:5b2a in the reproduced environment.
CPython classifies that outer IPv6 prefix as reserved, so the URL guard rejected
the request before examining the effective IPv4 destination.
Decode addresses in exactly 64:ff9b::/96 to their embedded IPv4 destination and
evaluate that destination under the strict outbound policy.
The translated target is always checked with private-address blocking enabled.
This prevents the NAT64 prefix from becoming a path to loopback, private,
shared/CGNAT, link-local, multicast, unspecified, or other non-global IPv4
space.
Network-specific translation prefixes are not decoded. In particular,
64:ff9b:1::/48 remains subject to the existing IPv6 policy.
Coverage includes:
- public IPv4 destinations embedded through the RFC 6052 prefix
- loopback, link-local, private, CGNAT, multicast, unspecified, benchmark, and
TEST-NET rejection
- network-specific NAT64 prefixes remaining undecoded
- deterministic scholarly provider tests without live DNS dependence
- redirect query parameter isolation
- relative redirect resolution
- HTTP error fallback behavior
- editor draft GET and DELETE behavior remaining unaffected
R09, R11, and R01 were independently audited and otherwise left unchanged.
* security(url-safety): reject RFC 6598 shared address space in strict mode
Strict mode (block_private=True) is a full SSRF lockdown, but it only
rejected is_private and is_loopback targets. CPython does not classify RFC
6598 shared/CGNAT space (100.64.0.0/10) as is_private (it is "shared", not
"private"), so a public redirect into 100.64.0.1 passed the per-hop guard
and still issued the request to a potentially internal CGNAT service.
not is_global would also exclude it, but only on CPython 3.11.10+/3.12.4+/
3.13+; the CI matrix runs 3.11/3.12, so reject the range explicitly to stay
correct across patch levels and the 3.14 runtime image. Default local-first
mode is unchanged. Adds strict-mode coverage for shared, non-global, and
public targets.
* docs(url-safety): correct CGNAT is_global rationale in strict-mode comment
The prior comment claimed `not is_global` catches 100.64.0.0/10 only on
CPython 3.11.10+/3.12.4+/3.13+. That is inaccurate for CGNAT: is_global
is False for 100.64.0.1 on every supported version (verified 3.10-3.14).
The version-fragility applies to other ranges gh-113171 touched, not CGNAT.
The explicit range reject is still the right choice; restate the reason as
is_private not covering shared space, and not coupling strict mode to
is_global's broader, cross-version definition. No behavior change.
POST /api/embeddings/endpoint takes a user-supplied URL and immediately
makes an outbound httpx request to it with no validation. The admin gate
added earlier (PR #80) closed the unauthenticated-access part of #132; this
addresses the remaining request: validate the URL before fetching it.
Odysseus is local-first, so pointing the embedding endpoint at a loopback or
LAN server (local vLLM / llama.cpp / Ollama) is a normal setup — a blanket
private-IP block would break the primary use case. So the guard:
- always rejects non-HTTP(S) schemes (file://, gopher://, ftp:// …),
- always rejects the link-local range (169.254.0.0/16, incl. the cloud
instance-metadata 169.254.169.254 exfil vector) plus multicast /
reserved / unspecified, and IPv4-mapped-IPv6 forms of the above,
- keeps loopback/LAN allowed by default, and
- adds EMBEDDING_BLOCK_PRIVATE_IPS=true for full SSRF lockdown on exposed
multi-tenant deployments.
Logic lives in src/url_safety.py (stdlib only, resolver injectable) so it is
unit-testable without real DNS; the route calls it before the health-check
request. Covered by tests/test_url_safety.py (8 cases).
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
