The channel delivered in 30 seconds: the nonce path went from 404 to 403 at
the edge, a near-miss path stayed 404 so the rule had not over-matched, and
the site root stayed 200 so nothing else had changed.
Withdrawal is a first-class operation here precisely because a patch written
in the hours after a disclosure is written against an advisory and not against
traffic. An empty rulesets array withdraws everything the channel owns, and
this exercises that path while nothing depends on it - which is the only
comfortable time to find out whether it works.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N5fpE6Gu4W6JoFMXyb7t7r
The channel shipped in engine 3.0.47 and has never carried anything: every
agent fetches cve.json hourly and skips it unread, because the build stamp has
not moved since 23/10. A mechanism that has never delivered a payload is not
known to work, and the day to find that out is not the day after a disclosure.
So: one rule for a path carrying a random nonce. No real client requests it,
nothing legitimate can match it, and it is anchored at both ends — checked
against the path itself and against three near misses before publishing.
This is deliberately NOT the five PHP patterns from engine 3.2.0. Every agent
in the fleet is already on 3.2.0, so those rules would add no protection, and
this document says why that matters: a feed rule and a compiled rule both add
to the same anomaly score, so one attack would be scored twice and reported as
two rules. Verified rather than taken on trust - rules.go accumulates in
eighteen places and ruleset.go:1354 adds to the same total.
Withdrawn as soon as it is confirmed enforced, which also exercises the
withdrawal path this channel treats as a first-class operation.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N5fpE6Gu4W6JoFMXyb7t7r
A deliberately temporary rule, to prove that a rule published through this
channel reaches every edge node and is enforced, and that withdrawing it
stops the enforcement. It matches a parameter name no real request carries.
To be withdrawn as soon as the test is recorded.
Validated against the engine's TestPublishedFeedDoesNotDuplicateACompiledRule
guard.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N5fpE6Gu4W6JoFMXyb7t7r
cve.json carries virtual patches: rules written against a named
vulnerability, published as data so that every edge node enforces them
within the hour instead of waiting for an engine release. Engine 3.0.47 and
later fetch it hourly.
It starts empty, which is a valid state and says "no virtual patches at the
moment" — the engine accepts an empty rulesets list as of 3.0.47, and
publishing one is also how the whole channel stands down.
Separate from rulesets.json rather than part of it: each has its own
build_datetime, so each is applied or skipped on its own, and a mistake in
one cannot take out the other. Publishing a patch should not mean
republishing a 357KB mirror of the Core Rule Set.
CVE-CHANNEL.md documents the format, the param_names target, how severity
becomes the anomaly score, and the two mistakes worth avoiding: publishing a
rule for a CVE the engine already patches in code (both fire and the scores
add), and forgetting that there is no backtest for a patch written in the
hours after a disclosure — which is why withdrawal is a first-class
operation here.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N5fpE6Gu4W6JoFMXyb7t7r
Andre
