GHSA-wrvw-254r-wpmv

### Impact An OS command injection vulnerability exists in the PowerShell and Cmd shell wrappers provided by the `CliInvoke.Specializations` package (the `PowershellProcessInvoker`/`CmdProcessInvoker` invokers, and the `UsePowerShell`/`UseCmd` middleware in v3 pre-release versions).

The wrappers re-run a caller-supplied target and arguments inside a shell command (`pwsh -Command ...` / `cmd /c ...`). In affected versions the wrapped command was delivered to the operating system as a single `ProcessStartInfo.Arguments` string. The OS command-line parser re-tokenizes that string before the shell parses it, so a double quote (`"`) in the target or arguments breaks OS-level quoting and lets the wrapped shell reassemble a second, unintended command.

An attacker could exploit this to execute arbitrary commands with the privileges of the host process.

### Patches The Specializations Packages now deliver the command via `ProcessStartInfo.ArgumentList` (natively where supported, and polyfilled in older TFMs), so that the operating system passes argv verbatim and only the shell parses the command once.

Upgrade to: - **2.8.5** (2.8.x line) - **2.9.4** (2.9.x line) - **2.10.5** (2.10.x line) - **3.0.0-beta.1** (3.x pre-release line)

### Workarounds No complete workaround is available. Until upgraded:

- Reject or strip `"` from any target path or argument passed to the PowerShell/Cmd wrappers. On 2.2.0 – 2.9.2 and 3.0.0-alpha.1 – alpha.4, also reject shell metacharacters (`;`, `|`, `&`, `$`, backtick, parentheses). - Alternatively, bypass the wrappers for untrusted input and invoke the target process directly so that no second shell parse of the data occurs.