Validate VERSION before writing to GITHUB_OUTPUT in monorepo-release workflow

[Copilot]

Summary

VERSION extracted from pyproject.toml in monorepo-release.yml was written directly to $GITHUB_OUTPUT without validation. A newline-containing version string (e.g., 1.0.0\nGH_TOKEN=leaked) could inject arbitrary key-value pairs into GITHUB_OUTPUT, poisoning subsequent steps. This also silently produced a tag named v if the grep/sed pattern failed to match.

Adds the same validation guard already present in python-release.yml, applied immediately after extraction and before any output is written:

if [[ ! "$VERSION" =~ ^[0-9a-zA-Z._-]+$ ]]; then
  echo "::error::Unexpected version format: '${VERSION}'" >&2
  exit 1
fi

Testing

• Not run (why?)
• uv run poe check
• Other: CodeQL scan — 0 alerts

Checklist

• Linked issue or task reference
• Added/updated tests where relevant
• Updated docs/README if needed
• No secrets or sensitive data added
• Considered backward compatibility and deployment impact

Additional context

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Validate VERSION before writing to GITHUB_OUTPUT in monorepo-release workflow to prevent newline injection</issue_title>
<issue_description>## Summary

The VERSION value extracted from pyproject.toml in .github/workflows/monorepo-release.yml is written directly to $GITHUB_OUTPUT without any format validation. A version string containing a newline character (e.g., version = "1.0.0\nGH_TOKEN=leaked") could inject arbitrary key-value pairs into GITHUB_OUTPUT, potentially poisoning subsequent workflow steps.

File & Location

• File: .github/workflows/monorepo-release.yml
• Line: 48

Original Review Comment

Category: CI/CD and GitHub Actions Security
Severity: Medium

The VERSION value extracted from pyproject.toml is written directly to $GITHUB_OUTPUT without any format validation. A version string that contains a newline character (e.g., version = "1.0.0\nGH_TOKEN=leaked") could inject arbitrary key-value pairs into GITHUB_OUTPUT, potentially poisoning subsequent steps.

By contrast, python-release.yml correctly validates wheel-derived values before using them:

if [[ ! "$NAME" =~ ^[a-zA-Z0-9_-]+$ ]] || [[ ! "$VERSION" =~ ^[0-9a-zA-Z._-]+$ ]]; then
  echo "::error::Unexpected wheel name/version format …" >&2
  exit 1
fi

Recommendation: Add an equivalent validation step immediately after extracting VERSION:

VERSION=$(grep -m1 '^version' pyproject.toml \
  | sed 's/version *= *"\(.*\)"/\1/')

# Validate format before writing to GITHUB_OUTPUT
if [[ ! "$VERSION" =~ ^[0-9a-zA-Z._-]+$ ]]; then
  echo "::error::Unexpected version format: '${VERSION}'" >&2
  exit 1
fi

echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
echo "tag=v${VERSION}" >> "$GITHUB_OUTPUT"

This also protects against an empty VERSION (if the grep/sed pattern fails to match), which would otherwise silently create a tag named v.

Proposed Fix

Add a format validation step immediately after extracting VERSION and before writing to GITHUB_OUTPUT, mirroring the pattern already used in python-release.yml:

if [[ ! "$VERSION" =~ ^[0-9a-zA-Z._-]+$ ]]; then
  echo "::error::Unexpected version format: '${VERSION}'" >&2
  exit 1
fi

---

Related PR: #51
Review comment: #51 (comment)

Generated by PR Review Comment — Create Issue for PR #51

Generated by PR Review Comment — Create Issue for issue #51

Comments on the Issue (you are @copilot in this section)

• Fixes Validate VERSION before writing to GITHUB_OUTPUT in monorepo-release workflow to prevent newline injection #73

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[Copilot]

Pull request overview

This pull request addresses a security vulnerability in the monorepo-release workflow by adding validation for the VERSION value extracted from pyproject.toml before it is written to GITHUB_OUTPUT. Without validation, a malicious version string containing newlines could inject arbitrary key-value pairs into the workflow output, potentially poisoning subsequent steps. The fix mirrors the existing security pattern already implemented in python-release.yml.

Changes:

• Added regex validation (^[0-9a-zA-Z._-]+$) for VERSION immediately after extraction and before writing to GITHUB_OUTPUT
• Added error handling that exits with status 1 if the VERSION format is unexpected