Read 2026-10-04
psf/black: technical due diligence, read from its repository
What Borehole read in psf/black's code and history at 8d5a2d9: its licence, security advisories, releases, review practice, tests, dependencies and operations. Every finding cites the file and line it rests on. The full report also covers the team and asks the questions the code cannot answer.
| Dimension | Rating |
|---|---|
| Architecture & Codebase — including AI provenance | strong |
| Engineering Process & SDLC Maturity | strong |
| Product & Engineering Maturity | strong |
| Security & Reliability Posture | adequate |
| Observability & Operations | not assessable |
| Fit with the Acquirer | not assessable |
Architecture & Codebase — including AI provenance
strongprofiling/list_huge.py is 22,432 lines, 448× this codebase's median file
adequateThe median source file here is 50 lines. 11 files exceed 1,000 lines, the largest being 22,432. Size is not a defect on its own — some problems genuinely live in one place — but these are where merge conflicts, review fatigue and single-owner knowledge concentrate, and they are the first thing that slows an inheriting engineer down.
profiling/list_huge.py:1 — 22,432 lines (448× median) |
profiling/dict_big.py:1 — 8,002 lines (160× median) |
profiling/list_big.py:1 — 4,001 lines (80× median) |
src/black/trans.py:1 — 2,662 lines (53× median) |
src/black/linegen.py:1 — 2,463 lines (49× median) |
Engineering Process & SDLC Maturity
strongNo finding.
Product & Engineering Maturity
strongNo finding.
Security & Reliability Posture
adequate1 Dockerfile runs the application as root
adequateNo USER instruction switches away from root, so the process runs with full privileges inside the container. It is a one-line fix and an ordinary expectation, which is why its absence is worth asking about: it usually says more about whether anyone has reviewed the deployment than about this container specifically.
Dockerfile — runs as root |
3 deserialisers that can run code
adequate3 places read data with a deserialiser that executes what it reads (pickle). That is safe on data the system wrote itself and remote code execution on anything else. Ask where each one's input comes from.
src/black/cache.py:80 — code-executing deserialiser |
src/blib2to3/pgen2/grammar.py:124 — code-executing deserialiser |
src/blib2to3/pgen2/grammar.py:129 — code-executing deserialiser |
2 advisories against this project in the last 24 months, 2 high or critical
adequateThe newest was published on 2026-03-12. A project that publishes advisories is telling its users about its fixes, and the count and pace say how much security work it carries. None of them affects the surveyed version. The record is incomplete: NVD: 46 records name black with nothing tying them to this repository (CVE-2002-0446, CVE-2008-2684, CVE-2008-3206, …).
| 2026-03-12: GHSA-3936-cmfr-pm3m (high), fixed in 26.3.1: Black: Arbitrary file writes from unsanitized user input in cache file name |
| 2026-03-06: PYSEC-2026-2120 (high), fixed in 26.3.0: |
Observability & Operations
not assessableNot rated: only 5 of 16 checks could reach a conclusion here; the rest do not apply to this repository or could not read it.
Fit with the Acquirer
not assessableNot rated: structurally not assessable from a repository.
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The full report on psf/black: every dimension, the questions for the room, and the audit log.
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