fix(updater): escape manifest-derived paths in the Windows update script - #580
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kdroidFilter merged 1 commit intoAug 19, 2026
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The Windows self-update PowerShell interpolates the downloaded artifact path into single-quoted strings (Remove-Item, Start-Process). That path is built from the `url` field of the remote update manifest, so a hostile or compromised manifest could embed a single quote to break out of the quoting and inject PowerShell that runs at install time. The macOS and Linux script builders already quote via quoteForShell(); the Windows builder did not. Every manifest-derived value is now passed through psSingleQuote(), which doubles single quotes — the PowerShell escape for a literal quote inside a single-quoted string — closing the injection while leaving ordinary Windows paths unchanged. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Security fix — F-6 (audit 2026-08-19)
Severity: Medium · Module:
updater-runtimeProblem
The
urlfield from the remote update manifest is used verbatim as the local artifact file name and then interpolated into single-quoted PowerShell strings with no escaping:A hostile or compromised manifest can put a
'in the name to break out of the quoting and inject PowerShell that runs at install time. The macOS and Linux script builders already escape viaquoteForShell(); the Windows builder had no equivalent.Fix
A
psSingleQuote()helper doubles every'— the PowerShell escape for a literal quote inside a single-quoted string — and every manifest-derived value (artifact path, script path, installer path, relaunch launcher) is passed through it. Ordinary Windows paths are unchanged; a'can no longer terminate the string and start a new command.Test
WindowsUpdateScriptTestgains a case feeding a name containingev'il; Start-Process calc.exe #and asserting the quote is doubled in the generated script and the raw break-out sequence never appears.Note (out of scope here): path traversal via a
../-containing manifest name is a separate concern in the staging-path construction (NucleusUpdater/FileSelector) and is best fixed there with a filename charset allow-list; this PR closes the injection (RCE) vector only.Verified locally:
:updater-runtime:ktlintCheck :updater-runtime:detekt :updater-runtime:testall pass.🤖 Generated with Claude Code