simplegit-rce-check

Offline evidence checker for CVE-2026-102826 — simple-git configuration include command injection.

It compares simple-git version evidence that you supply (CLI values, JSON/CSV inventories, npm lockfiles, installed manifests) with the reviewed advisory rules, and can list lexical source review candidates. It never contacts websites, imports application code, runs Git or a package manager, or executes exploit payloads.

• Scope and limits
• Requirements
• Quick start
• Synthetic report preview
• Version rules
• Operator observations
• Input modes
• Options
• Output and exit status
• Bounds and file safety
• Sources and references
• Development, security and license

Scope and limits

• Evidence triage, not a scanner. The checker covers only CVE-2026-102826 and assesses reported package-version evidence. A public URL cannot reveal an installed package inventory, and no network mode exists.
• Reported versions are claims. Obtain each deployed package instance's exact version and provenance. Declarations, lockfiles, manifests and local workstation versions are not deployment evidence.
• Nothing is exploited or verified in production. potentially_affected is not confirmed exploitability, and fixed_version_reported never attests an installed patch or safety. Every result retains exploitability: not_tested.
• Uncertainty stays visible. Missing, conflicting, malformed, prerelease, qualified, vendor/custom-built and uncovered-future versions are reported as unknown. unknown is neither a finding nor a clean result.
• Source inspection is lexical. It produces review targets only. No taint analysis, reachability test or runtime evaluation is performed.

Operate it only on evidence you are authorized to handle. Reports contain operator data; keep real targets, inventories and reports out of commits.

Requirements

• Python 3.10 or newer, standard library only; no installation step.
• The single file simplegit_rce_check.py can be copied and run alone. It bundles its own bounded input/reporting helpers and source lexer, and needs no companion repository at runtime.

Quick start

python simplegit_rce_check.py --version 4.0.0 --format json
python simplegit_rce_check.py --inventory examples/inventory.example.json --format html --output report.html
python simplegit_rce_check.py --csv-list inventory.csv --fail-on-finding
python simplegit_rce_check.py --help
python -m unittest -v

inventory.csv is your own file (see JSON and CSV inventories); the other inputs ship in examples/. The default output format is CSV on stdout. python -m unittest -v runs the local-only synthetic tests.

Synthetic report preview

Open the synthetic example report. Example data only; this is not a live assessment.

Version rules

The primary advisory and reviewed database were retrieved on 2026-10-24 (rules_as_of in every report).

Example reported version	Result
3.35.9	potentially_affected
3.36.0	potentially_affected
3.36.1	unknown
3.99.0	unknown
4.0.0	fixed_version_reported
4.0.1	fixed_version_reported
5.0.0	unknown

Do not invent affected status for hypothetical versions between 3.36.0 and 4.0.0. include.path and includeIf variants share this advisory.

Interpreting statuses

Status	Meaning
potentially_affected	The reported version is in the documented affected interval (up to and including 3.36.0). Application preconditions and exploitability were not established; this is not confirmed exploitability.
fixed_version_reported	The reported version is 4.0.0 or later within the reviewed 4.x fixed line. This describes a version claim only; it never attests an installed patch or safety.
unknown	Anything else: versions outside the affected interval and fixed line (no safety or other-vulnerability conclusion is made), future lines (no patch claim is extrapolated), and missing, conflicting, malformed, prerelease, qualified or custom/vendor builds.

Each row also carries a more specific version_status, such as in_documented_affected_range, at_or_above_fixed_version, outside_reviewed_range, version_not_disclosed, conflicting_versions, qualified_version_unverified, unrecognized_or_partial_version or vendor_build_unverified. The build_source value unknown (the default), upstream or official is compared as an upstream build; any other value, such as a vendor name, keeps the result unknown until independent patch evidence exists. Leading v prefixes are accepted.

Operator observations

Three optional observations describe advisory preconditions. They are supplied by the operator, unverified, and never change the package-version result.

Observation	Meaning
attacker_influence_over_clone_mirror_customargs	attacker influence over clone/mirror customArgs
attacker_controlled_readable_git_configuration_file	attacker-controlled readable Git configuration file
remote_operation_loads_unsafe_configuration	remote operation loads unsafe configuration

Each observation is boolean or null (not reported). Absent observations do not establish mitigation. Optional lexical source inspection is separate from them, and file-pattern findings show review targets, not proven input taint.

Input modes

At least one input is required. Modes can be combined in one run; every input produces its own rows. Unless noted, each input file must be named explicitly and is only read.

CLI versions

--version (alias --package-version) is repeatable. Each value is a separate instance, not evidence reconciliation for a single instance. --build-source and the observation flags (the observation key with underscores turned into hyphens, value true or false) apply to all CLI versions.

python simplegit_rce_check.py --version 3.36.0 --version 4.0.1 --format json
python simplegit_rce_check.py --version 4.0.0 --build-source "Example Vendor" --attacker-controlled-readable-git-configuration-file true

The second command stays unknown because the build is vendor-supplied.

JSON and CSV inventories

• JSON (--inventory, repeatable): one object or an array of objects. Required: integer schema_version: 1 and string package_version. Optional: package: "simple-git", label, build_source and the observation keys above. Unknown or duplicate keys, wrong types, non-finite numbers and malformed inputs are rejected.
• CSV (--csv-list, repeatable): requires a package_version column. Optional columns are label, build_source and the observation keys (true, false or blank). NUL characters are rejected.

A runnable JSON example is in examples/inventory.example.json.

npm lockfiles and installed manifests

python simplegit_rce_check.py --npm-lock examples/package-lock.example.json --format json
python simplegit_rce_check.py --installed-package path/to/node_modules/simple-git/package.json --format json

• --npm-lock reads explicitly named npm lock/shrinkwrap v1/v2/v3 JSON. Nested instances and aliases carrying an explicit package name remain separate. Metadata grammar follows the official package-lock reference, reviewed 2026-10-25. Lockfile URLs and scripts are not collected.
• Resolved versions are not proof of deployment. Linked packages, missing or qualified versions, conflicting primary/legacy lock records and unsupported coverage keep uncertainty, and conflicting version candidates are retained.
• When no determinable instance is found, the report includes an unknown coverage observation, never proof of absence.
• --installed-package reads only the name and version of an explicitly selected installed simple-git package.json, without running scripts or importing the module. Manifest metadata cannot attest that a serving process loads that package.

Lexical source candidates

python simplegit_rce_check.py --source examples/source.example.js --source-root examples --format html

--source explicitly selects JS/TS files (.js, .cjs, .mjs, .ts, .cts, .mts, .jsx, .tsx) and requires --source-root, which provides relative evidence locations and must contain every selected file. There is no directory traversal and no execution.

• Simple literal CommonJS/ES imports (default/named aliases and namespace simpleGit), factory calls, directly assigned client spellings, and clone/mirror argument shapes produce lexical review candidates.
• Factory config and actual call arguments are inspected separately; an unrelated same-file customArgs or config object cannot establish a flow.
• Argument labels describe literal containers/strings or dynamic expressions, not input trust. Identifiers named trustedConfig or request.body do not prove trusted input or attacker control.
• Shadowing, reassignment, computed syntax, templates (including interpolation), callbacks, chained methods, execution order and regex/division ambiguity require manual review.
• Source rows always remain unknown with not_tested exploitability and unfilled operator observations. They never inherit the status of a separately supplied version, manifest or lock instance.
• When no supported candidate is found, the report includes an explicit unknown coverage row rather than an absence verdict.
• Source strings and snippets, registry URLs and manifest scripts are not included in reports.

Options

Option	Purpose
--version VERSION (--package-version)	Assess an explicitly supplied simple-git version; repeatable.
--build-source SOURCE	Provenance of the --version builds (at most 512 characters): unknown (default, compared as upstream), upstream, official, or a vendor name.
--attacker-influence-over-clone-mirror-customargs --attacker-controlled-readable-git-configuration-file --remote-operation-loads-unsafe-configuration	Operator observation (true or false) applied to --version inputs.
--inventory FILE	JSON inventory object or array; repeatable.
--csv-list FILE	CSV inventory; repeatable.
--npm-lock FILE	npm package-lock/shrinkwrap JSON, lockfile versions 1, 2 and 3; repeatable. Never invokes npm.
--installed-package FILE	Installed simple-git package.json; repeatable.
--source FILE	JS/TS file for lexical clone/mirror candidates; repeatable. Requires --source-root.
--source-root DIR	Directory that must contain every --source file; evidence paths are relative to it.
--format csv|json|html	Output format; default csv.
--output FILE	Write the report to a new file; default is stdout.
--force	Explicitly replace an existing output file.
--brand NAME	Organization name shown in the HTML report (at most 512 characters); default CompleteTech LLC.
--fail-on-finding	Exit 1 when any result is potentially_affected.
--tool-version	Print the tool name and version.

Run python simplegit_rce_check.py --help for the authoritative option text.

Output and exit status

JSON, formula-neutralized CSV and escaped script-free HTML are rendered from the same assessments.

Format	Contents
JSON	One document with tool, tool_version, generated_at, report_schema_version, cve, rules_as_of, sources, complete and a results array.
CSV	One record_type=result row per asset observation. A zero-result report has a single record_type=summary row carrying completeness, schema, rule date, CVE and not_tested; it is not an asset finding. Every row carries tool, tool_version and generated_at.
HTML	Escaped, script-free report. Candidates and locations appear in escaped evidence notes.

Report schema 1.1 adds version_candidates, source_path, source_line, source_operation, source_argument_shapes, source_factory_options, source_config_argument and source_coverage to JSON and CSV. See docs/REFERENCE.md for the detailed reference.

generated_at is the UTC assessment-run time, captured once and retained after interruption. It is separate from rules_as_of, the advisory verification date. Evidence collection time remains unknown unless the operator records it independently; neither date attests deployment or installed patches. Embedding callers can inject generated_at into write_report for deterministic rendering across formats.

Exit status

Code	Meaning
0	Run completed.
1	At least one result is potentially_affected, and --fail-on-finding was given.
2	Argument, input or output error; operational failures are not assessment results.
130	Interrupted. Completed observations are written with complete=false when possible.

unknown does not trigger the finding gate and is not a clean result.

Interruption and partial results

• An empty interrupted CSV retains its summary row.
• An interruption after a complete report is published preserves that report and exits 130.
• An interruption while writing to stdout can leave a truncated document and never appends a second report.
• If an interrupt leaves file publication indeterminate, the checker exits 130 without retrying. Inspect the output before retrying; the diagnostic does not establish whether publication succeeded.

Bounds and file safety

• Only regular UTF-8 input files are accepted. Source files must resolve within the selected root.
• Limits: 4 MiB per file, 100 input files and 10,000 results per run, 512 characters per text field.
• npm lock traversal is limited to 64 dependency levels and 10,000 metadata entries. Source inspection is limited to 200,000 tokens per file and 4,096 tokens per inspected argument window.
• Output files are published atomically and are not overwritten without --force. Every input and its aliases stay protected from being overwritten, even with --force.
• Work from stable copies; file checks are not a filesystem sandbox.
• The checker performs no Git, npm, network, application or sandbox execution.

Sources and references

Primary advisory sources (retrieved 2026-10-24):

• https://github.com/steveukx/git-js/security/advisories/GHSA-g4wm-2vf7-vfgr
• https://github.com/advisories/GHSA-g4wm-2vf7-vfgr

Repository documents:

• docs/REFERENCE.md: detailed reference
• docs/IMPLEMENTATION.md: implementation status and verification checklist
• docs/example-report.html: synthetic example report
• AGENTS.md: repository instructions

Provenance of bundled code: the bounded input and reporting helpers come from the reviewed Node.js checker at commit 74aa57ba5df05c34d17ae67912cd26ec2335201b, with package-specific range comparison and the mixed-whitespace CSV fix. The source lexer comes from vm2-nesting-check commit 1618874 under the same licensing.

Development, security and license

Before changing the project, read AGENTS.md and CONTRIBUTING.md. Run python -m unittest -v, python simplegit_rce_check.py --help and git diff --check. Use synthetic evidence only and verify primary sources before changing version ranges. A local test pass is not a hosted CI result.

Report flaws in this project as described in SECURITY.md. The project is licensed under AGPL-3.0 or a separate commercial license from CompleteTech LLC; see LICENSE and LICENSING.md. Contribution terms are in CONTRIBUTING.md. CompleteTech LLC names, logos and the artwork in docs/images/ are brand assets and are not covered by the code license; see BRAND_ASSETS.md.