A 403 "egress DLP: URL-encoded CRLF (%0d%0a)" was firing on legitimate
requests (e.g. the Claude Code login flow) and bypassing the on-match
policy entirely, because CRLF blocks carry no matched value and were
routed straight to a hard 403.
Root cause: CRLF injection is only an attack in the request line and
headers. An HTTP body is delimited by Content-Length, so CRLF bytes in
the body cannot split the request — but the scan flattened the body into
the same blob it checked, so form-encoded / multi-line body content
(which legitimately contains %0d%0a) tripped it.
Fix:
- scan_outbound takes a crlf_text param; the addon scans CRLF only over
the body-excluded request line + headers. crlf_text=None keeps the
old full-blob behavior for host-side callers/tests; the websocket path
passes "" since a data frame is not a request line.
- The redact policy now also scrubs CRLF (new strip_crlf helper) from the
path and headers, so redact is a complete escape hatch and structural
CRLF in the URL/headers can be forwarded when a route opts into it.
Tests: strip_crlf unit tests; scan_outbound crlf_text body-exclusion and
backward-compat tests.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HnvBjPZC5V7qeQpFbQdDmS
When the outbound DLP catches a token, route the block through the
existing supervisor approval queue instead of returning 403 outright.
The egress proxy holds the request open until the operator answers, then
remembers an approved value for the life of the proxy so the request --
and later ones carrying it -- flow through. Fails closed on rejection,
timeout, malformed response, or when supervise is disabled.
- ScanResult.matched carries the raw matched substring (sidecar-only;
never logged or written to the proposal). scan_outbound and the token
detectors take a safe_tokens set and skip approved values, continuing
past a safelisted match so a second secret in the same request is
still caught.
- New egress-token-allow proposal tool, written directly to the queue by
the addon (the gitleaks-allow pattern from PRD 0061). build_token_allow
_payload renders host/method/path/detector reason + redacted context.
- Async request hook polls the queue without stalling the proxy event
loop; EGRESS_TOKEN_ALLOW_TIMEOUT_SECONDS (default 300) bounds the wait.
- Supervisor TUI renders egress-token-allow like gitleaks-allow: report
only, modify unavailable, approval requires a recorded reason.
- Unit tests for the matched/safe-tokens plumbing, payload builder, tool
constant round-trip, and TUI paths; README + PRD 0062.
Closes#261.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HnvBjPZC5V7qeQpFbQdDmS
Each DLP block/warn now reports where the match was found (body,
authorization header, response body) and includes a context snippet:
SNIPPET_CONTEXT chars before and after the match, with the matched
value replaced by REDACT ("********").
scan_token_patterns/scan_known_secrets/scan_naive_injection all gain
`location` and `context` fields on their ScanResult returns. The
outbound scanner takes `auth_header` as a separate kwarg so the two
locations are scanned and reported independently.
redact_tokens() is added to dlp_detectors and used in egress_addon.py
to scrub token patterns and provisioned secrets from host/path fields
before they appear in any log output (level 1 and 2).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Token detection is already handled by the token_patterns detector
running separately — calling it again from scan_naive_injection was
redundant. New logic:
- Warn on any disclosure phrase
- Warn on any jailbreak phrase
- Block when both appear within 500 chars of each other
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
didericis
didericis-claude