Three directions recorded, each grounded in what this session measured. **WordPress by flaw class, not by plugin** (tasks 5.8, 5.9). One plugin is a checkout; a class is a claim. WordPress's recurring shapes are narrow and each maps to a family that already exists -- unauthenticated wp_ajax_nopriv reaching $wpdb, a missing capability check, unescaped output, arbitrary file operations. Two of the four are blocked on gaps this session found: access control cannot be asked at all because PHP has no obligation facts (5.9), and unescaped output is blocked on the flat sanitizer list (5.6). The observable is a class-by-class table across several plugins saying found, missed, or out of scope -- a single found CVE is not the artifact worth teaching from. **Why a corpus of benchmarks is not enough on its own**, written into overview.md as the finding it is rather than an opinion. Twelve engine defects in one session against three real repositories, and the three gates stayed byte-identical through every fix. A gate that does not move is a corpus that could not see the bug. The reason is structural: a pair is a labelled function with a declared family and a known answer, so it cannot exercise which region to look at, what to spend, whether a capability is reachable, whether two entry points share a sink, whether the question fits in an argv slot, or whether a flow crosses a module. Three of the twelve were quiet failures where the tool reported clean and every honesty counter agreed -- which a benchmark score cannot express, because the score is computed from the verdicts that exist. The corpus is the holdout that stops per-repository tuning, and the wrong instrument for finding out whether the tool works. **ir-consolidation** (brief, unapproved) separates two questions the IR suggestion contains, which have opposite answers. The SOURCE IR is already carried rather than about to be added: semantic/ is 3218 lines, 16% of the codebase, measured at 2.2% entailment against the CPG's 41.3% and still running as a proposer -- and Vine and P-Code are binary IRs, so the work there is subtraction. The MISSING abstraction is C arithmetic, and there GhidraPAL's three-valued-logic abstract interpreter over Ghidra P-Code is exactly the right shape: "can this index exceed this allocation" is a value question, which is what a bit-level TVL domain answers and what every libpng overflow needs. Vine is dormant since 2009 and is not the candidate. The constraint is recorded as an ordering: question 1 lands before question 2 starts, or adopting an IR makes the growth problem worse. And the cost that matters is not lines but the number of things that can silently return nothing -- this session found three such in a single PHP scan, and a binary pipeline adds a build, a lifter and a domain, each able to produce an empty result that looks like a clean one. Co-Authored-By: Claude Opus 5 (1M context) <[email protected]> Claude-Session: https://claude.ai/code/session_01T7XD7x5KonMdmGRkp63EQG
8.3 KiB
Overview — what this is, and what is actually true of it
Written 2026-09-09. Fourteen specs have accumulated and the roadmap still described a pre-Joern world, so
this is the synthesis above them: what the system does, what has been measured, and what is not true yet.
Every number here comes from a committed artifact in benchmarks/measurements/.
What the tool is
A static analyser that separates what it can prove from what it merely suspects, and says which is which.
The thesis is not the dataflow engine — CodeQL and Semgrep have one and developers do not turn it on. It is the rung: a claim you can act on without writing a query, and an explicit admission when the engine could not decide.
execution_confirmed a test or sandbox reproduced it (built, no production caller)
model_entailed the graph decided: a flow with no discharge,
an obligation with no guard, a permissive value ← the product
model_corroborated the graph found the shape; a judge with
coverage agreed on the residual question
suspicion an enumerator or a pattern proposed it and
nothing corroborated it ← everything below the line is noise
until proven otherwise
Silence is not a clean bill of health. If no fact table covers a site, the model is silent, not negative — 23 of the 39 misses in the original entailment ceiling were sinks simply absent from the tables.
How it works, in one pass
preprocess ─▶ entry-point map ─▶ MAP stage ─┬─ static patterns
├─ semantic overlay
├─ obligations (absence bugs)
├─ tool hunter (LLM)
└─ MODEL LAYER ──▶ one CPG per repository (Joern, subprocess)
├─ taint reachability + sanitizer lattice
├─ dominance guard governs obligated operation
└─ config constant abstraction over a value
Three abstractions, one arbiter each, dispatched on spec type so a family without an arbiter cannot be silently routed to the wrong one. The CPG is built once per scan and every question is batched into one invocation per query kind.
What has been measured
| measured | source | |
|---|---|---|
| entailment, flat IR → CPG | 2.2% → 41.3% of the corpus | 2026-09-08-model-entailment-ceiling*.json |
| vibe-py pairs (30) | 90.0% pair-correct, 6.7% leak, $0.0068 | 2026-09-08-pipeline-vibe-py.json |
| — against the LLM hunter | 76.7% / 12.3% at 5× the calls, ~100× the cost | same |
| vampi (python, 520 lines) | 3 of 3 known vulnerabilities at model_entailed |
2026-09-09-repo-vampi-authz-precision.json |
| vampi access-control precision | 28.6% → 50.0% | same |
| access-control leak, pairs nobody tuned against | 42.9% → 0.0%, pair-correct unchanged | same |
| libpng envelope (89k lines of C) | build 16s, query 250s, scan 446s, 911 MB | 2026-09-09-repo-libpng-envelope.json |
| libpng valid findings | zero | same |
| report proportionality | libpng 198 sections → 39 | 2026-09-09-report-proportionality.json |
What is not true yet
- The C story does not work.
c/memoryhas produced zero true positives and three distinct classes of false one. It models string functions; libpng overflows through arithmetic, and its library code never calls a sink we model. This is structural, not tuning. - One language is demonstrated. Python. JavaScript has fact tables and pair coverage but no repository. PHP, Ruby and Go have zero families — Joern would parse them and the engine would say nothing.
- The suspicion band is still too loud. vampi emits 61 report sections for a 520-line application, 38 of them a candidate the graph could not decide with a judge's opinion attached.
- The evidence base is two repositories. One has never produced a true positive.
- Control dependence is unavailable. 0 of 13,184 calls in the libpng CPG and 0 of 1,152 in vampi's have a controlling control structure, so every guard question runs on CFG dominance instead.
execution_confirmedhas no production caller. The rung exists and nothing reaches it.
Why a corpus of benchmarks is not enough on its own
This is the finding worth teaching, and it is not an opinion — it is what the gates say.
Twelve engine defects were found in one session by pointing the tool at three real repositories. The three gates stayed byte-identical through every single fix. A gate that does not move is a corpus that could not see the bug.
| defect | what the corpus saw |
|---|---|
resolve matched inside resolveUrl (sanitizers) |
nothing |
user matched inside users (dischargers) |
nothing |
gets matched inside fgets (sinks) — 26 identical false positives |
nothing |
| the model layer had zero production callers | nothing |
query_batch implemented, tested, unreachable |
nothing |
| a paid budget halting unpaid arbitration | nothing |
| a region with no function claiming the whole repository's answer | nothing |
| a guard discharging an obligation it is not a guard of | nothing |
joern-parse failing where the frontend succeeds |
nothing |
| a 1.49MB batch over Linux's 128KB argv cap | nothing |
| an array callable not recognised as a handler | nothing |
| one defect reported as twenty-six findings | nothing |
The reason is structural rather than a gap in the corpus's coverage. A pair is a labelled function with a declared family and a known answer. It cannot exercise: which region to look at, what to spend, whether the capability is even reachable, whether two entry points share a sink, whether the question fits in an argv slot, or whether a flow crosses a module boundary. Every one of those is a property of a repository, and none of them is a property of a function.
Three of the twelve are worse than invisible — they are quiet failures, where the tool produced a clean report and every honesty counter agreed with it. The rung ladder labels a verdict; when no verdict is produced there is nothing to label. That is the failure mode a benchmark score cannot express at all, because the score is computed from the verdicts that exist.
So the corpus is necessary and not sufficient: it is the holdout that stops per-repository tuning, and it is the wrong instrument for finding out whether the tool works. Both instruments, or neither number means anything.
The lesson that shaped the current specs
Nine engine defects were found in one session by pointing the tool at two real repositories. Three were the
same bug in three matchers — a spec token matched as a substring: resolve in resolveUrl, user in
users, gets in fgets. Two were a capability built and unreachable: the model layer itself, then the
query batcher. One was a paid budget stopping unpaid work.
The three gates stayed byte-identical through every one of those fixes. That is the finding: a corpus of function-level pairs could not see any of them, and a repository showed all nine within minutes.
Where the specs stand
| spec | phase | state |
|---|---|---|
contributor-scan |
implementation | 14 done, 15 open — the active one |
finding-feedback-loop |
design | requirements approved, design awaiting approval |
model-grounded-detection |
complete | 16/16; built the arbiter this all rests on |
authorization-obligations |
tasks approved | 24 open — superseded in practice by the dominance arbiter |
constrained-detector |
tasks | 4 of 20, tasks unapproved |
reachability-flow-model |
tasks generated | 23 open, nothing approved — largely delivered by adopting Joern |
learning-harness |
implementation | 30 done, 3 open |
| six others | complete | pair-corpus-honesty, corpus-seeded-mechanisms, propose-adjudicate-prove, three-stage-scan, real-world-vfc-slice, harnessx-self-improving-rulesets, tree-sitter-overlay-extra |
97 source modules, 90 load-bearing and 7 standalone capabilities; 814 tests.