Adam Moussa 7c74ac1761 Harden AR parsing and alarm on sender-auth rejects ... The SES-stamped Authentication-Results value echoes attacker-controlled SMTP-session tokens (envelope-from, helo, header.from) as their own semicolon-delimited property clauses. A naive split(";") tore an RFC 5321 quoted-local-part MAIL FROM apart and manufactured a forged dkim=pass clause, so a fully spoofed email was accepted on the genuinely SES-stamped topmost header. Tokenise comment- and quoted-string-aware (RFC 8601 / RFC 5322): strip CFWS comments, split clauses only on semicolons outside a quoted-string, and fail closed on unbalanced quotes/comments so a ';' inside a quoted pvalue can never start a clause. Rejected mail returns normally (no error, no retry, no DLQ message), so a signing-domain drift or a wrong allowlist would silently discard 100% of legitimate mail while every alarm stayed green. Add a CloudWatch Logs metric filter + alarm on the sender_auth_rejected warning to both stacks so a false-reject storm pages instead of vanishing. This is also the safety net for the WO seahaven.com allowlist assumption, which must be validated against a live SES-stamped header (a plain Gmail auto-forward re-signs under the sending Workspace domain, not seahaven.com). Refs: INFRA-107		2026-07-15 19:13:55 -04:00
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conftest.py	Add fail-closed SES sender authentication	2026-07-15 18:53:46 -04:00
test_ses_auth.py	Harden AR parsing and alarm on sender-auth rejects	2026-07-15 19:13:55 -04:00