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3 commits

Author SHA1 Message Date
Hound
2cf9a740c3 rules: every rule needs an anchor, and the test now proves it for all of them
Stage 3 passed on throughput — 27,339 events, zero rescues, Caddy
unmoved — and then the soak found what the load test could not.

Two more false positives, both the same shape as the ones before:

* EICAR matched an 8.5 MB rustc incremental-compilation cache, because
  the test source being compiled contains the literal. Hound moved it to
  quarantine mid-build and rustc panicked. The standard defines the
  EICAR file as exactly that 68-byte string, optionally padded to 128,
  so the rule now says filesize <= 128.

* The webshell rule matched a 4.3 MB AI session transcript, because the
  conversation had been discussing webshells and therefore contained
  "<?php", the eval pattern and "$_POST". The transcript was moved to
  the vault and its history lost. A webshell is a PHP file: small, and
  opening with a PHP tag. Now filesize < 1MB and $php in (0..4096).

The interesting part is why the second one happened at all. After the
first, I added a test asserting that a large file containing rule
strings is not a threat — and hand-listed the strings. I listed the
miner's and the rootkit's and forgot "<?php". The test passed and the
transcript was quarantined anyway.

So the test now extracts every string literal from the rule pack itself
and builds the haystack from those. A rule added tomorrow is covered
without anybody remembering to cover it. It also asserts the extractor
actually found the strings, because a parser that silently returns
nothing would make the whole thing vacuous.

Both fixes have a paired test that the detection still works: a real
68-byte EICAR file is caught, padded to 128 it is caught, and a real
webshell is caught.

Worth recording, because it is not a bug: six houndd tests failed while
the gate was armed. Hound quarantined the EICAR fixtures the test suite
had just written — correct behaviour, colliding with a suite that
creates real malware samples. Running the antivirus's own tests on a
gated machine needs thought; the tests are not wrong and neither is the
gate.

The definitions chain now works end to end: pack built from OSV, signed
with the release key, published to /srv/houndav/defs, installed, and
verified on load against the public half compiled into the agent —
"defs: 19 indicators from 1 pack(s) [2026.08.21]".

The public key is in the source on purpose. The agent is open source and
anybody should be able to check that the definitions they received are
the ones we published.

300 tests pass. Gate is off pending these fixes being soaked.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-21 08:37:49 -05:00
Hound
42cd97d59f supply: read lockfiles, and only ever call a malicious package malicious
Lockfile parsing for npm (all three lockfile versions), yarn, cargo,
poetry, requirements.txt, go.sum, Gemfile.lock and composer.lock, wired
through the indicator index so a sweep checks real dependencies against
real definitions. Signed packs load in the daemon; the sweep gets the
index; `hound supply-chain` cites the OSV record it matched.

A lockfile is the right thing to read: it names every transitive
dependency at an exact version in one small file, and it lists what WILL
be installed rather than what already is — which matters when the
payload runs during installation.

Every parser is hand-written rather than pulling in a TOML and a YAML
crate. Two fields from each format, and a scanner parsing hostile input
should have as little parsing surface as it can.

The important part of this commit is a false positive it fixes.

Building a pack from the whole crates.io OSV export and sweeping a
project produced TWO criticals: rustdecimal, correctly, and **tokio
1.38.0**, which is not malware and never has been. The export is 1,524
GHSA and 1,206 RUSTSEC vulnerability advisories against 19 malicious-
package records, and the parser treated all of them as malware.
GHSA-2grh-hm3w-w7hv describes a tokio race condition fixed in 1.8.1;
Hound reported a version released years later as malicious.

Two independent bugs, either of which alone is fatal:

* Vulnerability advisories were ingested at all. A malicious package
  should not exist; a vulnerable one is a legitimate library with a bug
  and most of its versions are fine. Records must now PROVE they are
  malicious-package reports — a MAL- id, the malicious-packages-origins
  marker, or GHSA's "Malicious code in" wording — and anything
  unrecognised is dropped.

* Unrecognised version ranges fell back to "all versions", which is the
  opposite of safe. That is what turned a range of 1.8.0-to-1.8.1 into
  a verdict on every tokio ever published.

Rebuilt against the same input, the pack now holds 19 indicators rather
than 3,614, rustdecimal is still caught and cites MAL-2022-1 rather than
a GHSA advisory, and tokio and serde are clean. The real tokio advisory
is now a regression fixture, because anything that flags tokio is a
product nobody trusts twice.

Also: definitions loading fails CLOSED on authenticity and OPEN on
everything else. No trusted key means no definitions and a message
saying so, because an operator who believes they are protected and is
not is worse off than one who knows. A pack that fails verification is
skipped and the rest still load. No packs at all is a working daemon —
install scripts, prompt injection, pickles and MCP audits need no feed.

There is deliberately no placeholder signing key compiled in. A fake key
that looks real is how a development shortcut becomes a shipped
vulnerability; an empty trust store is noisy in the way that gets fixed
before release. HOUNDD_DEFS_KEY supplies one for development.

294 tests pass across the workspace.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-21 07:29:47 -05:00
Hound
3be16eeef9 hound-defs: OSV ingest, the IOC index, and signed packs
Phase 3's foundation. Three jobs that share a data model:

  osv    parse the ossf/malicious-packages feed (Apache-2.0, ~226k
         records, daily) into indicators
  index  answer "is this package known bad?" fast enough to ask it
         thousands of times per project sweep
  pack   sign a definitions pack, and verify one before loading it

Validated against the real feed rather than fixtures: the whole
crates.io OSV export, 2,749 records, parsed with zero failures — 3,885
indicators across ten ecosystems, 19 of them MAL-. `rustdecimal` (the
real typosquat of rust_decimal) resolves in crates.io and stays clean
in npm and PyPI, which is the ecosystem isolation working.

Notes on the three:

* A malicious-package record is not a vulnerability record. It almost
  always carries introduced:"0" with no fix, meaning EVERY version is
  malicious — the package exists only to be malware, so there is no safe
  version to upgrade to. Conflating that with a version-bounded
  vulnerability either misses real hits or condemns safe versions of
  legitimate packages, so the two are modelled separately.

* The index is a cuckoo filter in front of a map. Cuckoo rather than
  bloom specifically because a definitions feed needs DELETION: OSV
  withdraws records — it once withdrew 157 malware reports after a
  false-positive incident — and a filter you cannot remove from means a
  withdrawn record costs a probe forever or forces a rebuild. 226k
  indicators fit in under 4 MB; the crates.io set is 8 KB.

  The property that must never break is no false negatives, and it has
  its own test. A false positive costs a hash lookup; a false negative
  is malware reported as clean. That is also why a fingerprint hashing
  to zero is nudged to one — zero marks an empty slot, so without the
  nudge one key in 65,536 would silently vanish.

* Signing is not about entitlement; the subscription gates the server.
  It answers "is this pack really from us?", because someone who can
  substitute a definitions file can add an entry for /usr/bin/sudo and
  have Hound quarantine it on every machine that updates — a supply
  chain attack delivered through the security product. Verification
  happens on the raw bytes BEFORE anything parses them, so a hostile
  pack never reaches the parser at all.

256 tests pass across the workspace.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-21 07:06:00 -05:00