FUXA failed every hunt with HTTP 400, and neither run could say why. The client
discarded the response body. With the body shown, the reason was "This model's
maximum context length...": FUXA ships minified bundles whose single lines run to
megabytes, and grep_repo returned a matched line whole.
- grep_repo and find_refs quote a matched line (240 characters), never the whole
line.
- Every tool result is capped at 16 x max_chars, with a truncation marker.
- OpenRouterChatClient errors carry the provider's response body (first 500
characters). That would also have exposed the rejected model id in one call
instead of eighteen days.
After the fix, FUXA candidates verify normally at $0.004-0.013 each. A test covers
the megabyte-line case.
verify_sinks.py: skip futures cancelled at the spend ceiling instead of reading
them (the run crashed with CancelledError).
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Each grep_repo and find_refs call re-enumerated the tree (walk, ignore rules,
vendored checks) and re-read every file. The v2 sink verifier spent almost three
hours on its first case (pgAdmin, about 1,800 files) at 108% CPU with one open
connection. It was CPU-bound in these tools, not waiting on the model.
Source lines are now memoised per root, keyed by path and modification time. A hit
is re-validated file by file, because an edit inside a subdirectory does not touch
the root's mtime; a test covers one enumeration and a detected edit.
verify_sinks.py now runs candidates in worker processes, not threads, and appends
each candidate's result to a per-case log, so a stopped run resumes where it left
off. GoPay: 12 candidates in 14 s, the real site found.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Per candidate function, one bounded tool-hunter pass (custom prompt, the file as
context, 3 steps) asks whether attacker-controlled data reaches the operation
without a sufficient guard. It reports only with a stated source-to-sink path.
Hard spend ceiling, parallel workers; one run per pin; the fixed pin is rechecked
only for detected sites. Exploratory on v2.
Pilot: on GoPay, the one real site was reported in 3 of 4 runs and nothing else
out of 12 candidates.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Source-only selection on the v2 vulnerable pins, compared on the same cases:
- ranker top-20 entry points: the vulnerable file was in scope in 1/17;
- shipped-vocabulary sink-first: the declared site was a candidate in 2/17;
- model-classified sinks (deepseek-flash, no vocabulary): the declared site was a
candidate in 15/17, and a fix or site file in 16/17. Every chunk was classified;
$14.42.
Misses: User Registration (file in scope, not the function) and Sulu (JCR-SQL2
query builder). The cost of this reach is volume: 3-1037 candidate functions per
repository, 4,762 in total. The next stage must decide which candidates are fed by
attacker data without a guard. v2 is spent for tuning; this qualifies nothing.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
This asks DeepSeek, per product source file (in chunks of 400 numbered lines),
which functions perform the family's dangerous operation on non-constant data. It
is scored like sink_candidates.py: is the declared vulnerable function among the
candidates? A failed chunk counts as unclassified, never as "no sinks". The spend
ceiling is enforced across worker threads.
Pilot: GoPay found its declared site for $0.03. Estimated full v2 run: ~$14-18.
The maintainer raised the ceiling to $20.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
This is a source-only diagnostic: no engine and no model. At each v2 vulnerable
pin, every call matching the family's shipped sink vocabulary becomes a candidate,
attributed to its enclosing function.
- The declared vulnerable function is a candidate in 2/17 cases (Medplum, GoPay);
the ranker's top 20 managed 1/17.
- A fix-changed or site file is among the candidates in 8/17.
- Candidates per repository range from 2 to 904 functions.
The misses are vocabulary, not direction. Examples: wp_redirect, download_url,
spawn(shell:true), ky(), requests.Session().get, sympy parse_expr, Jinja
from_string().render, Mongo collection.find, JCR-SQL2 createQuery, TypeORM
andWhere template strings, and CORSMiddleware(allow_origins=["*"]) are not named.
v2 is spent for tuning, so this informs design and qualifies nothing.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
The run follows hunter-protocol-v2.md: deepseek-flash, the ranker's top 20
regions per pin, protocol v2 scoring, $8.88 spent.
- Recall: 1/17 (Wilson 0.01-0.27).
- Precision: 2/14 sampled (both true positives need a privileged role, one of
them GoPay's CVE).
- Fixed-side alerts: 1. Benign alerts: 16.
- Stability: 73% of findings differ between two identical runs.
The deciding observation: the ranker's top 20 contained the vulnerable file in 1
of 17 cases, and in that case (GoPay) the hunter detected it. With 4 tool steps
per hunt it cannot search its way to code it is not handed. The result therefore
says less about the model than about scope selection, which sits upstream of the
engine too.
Instrument failures, reported as failures: every FUXA pin and three Directorist
pins (DeepSeek HTTP 400 on every hunt; neither offered a region of its family).
Scorer fix: protocol v2 defines benign alerts and the precision pool over the
CASE FAMILY, but score_v2 pooled every family. The engine's dump emits only the
case family, so its recorded result (21adc40) is unchanged by this; rescoring
reproduces 3 benign alerts and 49 pooled findings.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
This is the deciding experiment of the strategy review, fixed before any v2 pin is
hunted.
- Hunter: the unchanged tool hunter (default prompt, tools and 4 steps) on
deepseek-flash.
- Scope: the ranker's top 20 regions for the case family, in four hunts. The model
never sees the fix diff or the declared sites.
- Families: a fixed keyword table maps the model's family to the protocol's three.
- Scoring: exactly protocol v2's scorer.
- Cost: a hard $10 ceiling.
hunt.py runs it and scores it (--score). A pilot on a v1 development case
(mongo-express) found the vulnerability at lib/bson.js:60, at $0.031 per pin,
alongside a lot of speculative noise.
Transport fix found by the pilot: the DeepSeek endpoint the hunter builds was
unpriced, so the cost meter read $0.00 for any number of calls. It is now priced.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
The analyzer was frozen at a75b9f6. 17 cases, 102 scans (vulnerable and fixed pins
twice each), scored exactly as pre-registered.
- Recall: 0/17 (Wilson 95% 0-0.18). No unstable detections.
- Precision: 0/17 sampled (0-0.18). Every sampled finding is false: regex
match/exec read as sinks, int casts, ORM statements, client-SDK code, the
process's own argv, a generated database name, a registered-URI check.
- Completion: 13206/108374 questions (12%).
- Fixed-side alerts: 0, trivially, since nothing was detected.
- Benign alerts: 3.
- Stability: 2 of 100 findings differ between runs.
The zero is not an instrument artefact: FUXA, GoPay, cct-studio, ReactPress, User
Registration and Directorist completed questions in the sink file itself and still
found nothing.
Instrument failures, reported as failures: LMDeploy (every taint batch failed on all
six pins) and Froxlor's two benign scans.
This record is committed before any analyzer change informed by v2.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Committed before any v2 case is scanned. It has two changes from v1, both chosen by
the maintainer from lessons of the v1 run:
- declared sites: a finding at a `path::function` the advisory names is credited,
as well as one on the fix's changed lines;
- two runs of the vulnerable and fixed pins: detection needs the finding in both
runs, a fixed-side alert in either counts, and the difference between runs is
reported as stability.
evaluate.py takes --population. v2 scans six pins per case and scores with
matches_v2 / score_v2. v1's scoring is unchanged.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
The analyzer was not run. freeze.py read each case's source at both pins:
- both pins are commits in the repository and in the right order;
- the declared sink site's file is present at the vulnerable pin, and its declared
functions appear in it;
- the fix touches a declared site file (Budibase's sites reordered so the changed
file, queries.ts, comes first).
Benign controls:
- 12 are reviewed automatic proposals.
- 3 automatic proposals were rejected as not benign: qwed's merged a ReDoS fix,
ReactPress's corrected a SQL column whitelist, and Sulu's was a branch merge that
can carry the fix.
- Those three, plus cct-studio and Directorist (no automatic proposal), were chosen
by hand. Directorist's comes from before the vulnerable pin, because only 3
commits follow its fix.
freeze.py now accepts a recorded benign control instead of reporting that none was
proposed.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
v1 was evaluated and then used to retune the analyzer. A retune can only be
qualified on a population that did not inform it.
The candidates came from web research alone (research-2026-09-26.md):
- advisories were taken newest-first per language under fixed criteria, never by
how easy they look;
- 261 advisories were examined and 224 rejected, each with a reason;
- every SHA pair was verified through the GitHub API;
- no clone and no scan.
The maintainer selected the rule-based "balanced" set: 5 Python, 6 JS/TS, and 6 PHP
of which 4 are WordPress plugins; 10 injection, 6 destination and 1 config.
Each case declares the advisory's sink sites before any scan, for protocol v2.
freeze.py takes --population and writes freeze-vN.json. The reservation tests now
cover every population-v*.toml.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Scored exactly per the pre-registered protocol-v1.md, analyzer ebcc2cf,
44 scans on eleven untouched cases.
Recall 1/11 (95% CI 0.016-0.377): only Signal K's SSRF sink is detected.
Precision 1/12 on the full pooled sample: the other eleven findings are
guarded redirects (isSafeRelativeUrl, getSafeDestination), Host-header
redirects, constant SET NAMES queries, a config-file eval and an installer.
Four fixed-side false alerts (mongo-express bson.js, both wger sinks after
their guard was added) and one benign.
The dominant cause is coverage, not precision: at the vulnerable pin eight
of eleven cases completed ZERO questions and Saltcorn asked none, so most
targets were never decided. Recorded before any investigation or change.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Committed before any case is scanned: what is under test (the analyzer at the
runner's commit, per-case family only, four scans per case), how a finding
MATCHES a case (a fix-changed file, the case family, the named function or
within 10 lines of a fix hunk), detection / fixed-side / benign false alerts,
unanswered and instrument failures, the precision sampling rule (every third
pooled vulnerable-pin finding, or all if 15 or fewer), what is reported
against the M4 gates, and that no retune may be informed by the results.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Every reserved case verified with git and file reads only -- nothing
scanned: pins present and ordered, the sink present at the vulnerable pin,
the fix touching the sink (or LearnPress's declared source-side fix site),
and the sink file hashed at both pins (benchmarks/independent/freeze.py,
record freeze-v1.json).
Each case now carries a benign control from its own history, reviewed by
diff. The mechanical keyword filter was not enough: it proposed an access
restriction, a filter check, API-token scopes, a login change and a
TLS-verification option, all rejected; Ultimate Member and alerta got
hand-picked controls (a WPCS reformat; a dependency change with both sides
still vulnerable). The guard test requires a benign pair per case once
frozen.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
Eleven cases chosen by the maintainer from fifteen researched by advisory
and fix diff only -- nothing cloned, nothing scanned, none among the 262
repositories the benchmarks reference -- plus the earlier Ghost
reservation. Four are PHP repositories that ship JavaScript (two WordPress
plugins), satisfying the multi-language requirement; families are limited
to the v1 scope (injection, untrusted destination, permissive config).
The development subjects shaped every rule of the last week and can no
longer measure whether those rules generalise; this population can, until
something scans it. A guard test fails the moment a reserved repository is
referenced by a recipe, catalog, manifest or measurement outside
benchmarks/independent/. Freezing (pins and sinks verified by reading
source, a benign change per case) is the next step.
Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo
