# Adversarial Bug Report: parametrize-base-branch

## A1 — Git injection via base_branch value

`base_branch` values like `"; rm -rf /"` or `"main\norigin/main"` are passed through to `subprocess.run` in list mode. The entire value is a single argv element — no shell expansion, no injection. Git will attempt to resolve the string as a revision name and fail (fatal: bad revision), which triggers the WARNING-skip path. No exploit.

**Verdict**: no vector. List-mode subprocess.run is safe by construction.

## A2 — Non-string base_branch (int, bool) coerce to string

`42` → `"42"`, `True` → `"True"`. Both are valid git ref names (a tag named `42` or `True` would resolve). The WARNING notifies the operator. No crash, no silent misbehavior.

**Verdict**: acceptable. The WARNING is a signal to fix the config.

## A3 — Empty base_branch falls back to main

`""` → `"main"` with WARNING. Operator typed it intentionally or accidentally; either way the drift gate works on `main`. No data loss.

**Verdict**: correct per D-B4.

## No BLOCKERS

Proceed to doc_review.