8.4High

CVE-2026-100368

CliInvoke is a .NET library for invoking command-line programs, and its `CliInvoke.Specializations` packages provide specialized wrappers for shells such as PowerShell and Windows Command Prompt. `CliInvoke.Specializations` versions 2.2.0 through 2.8.4, 2.9.0 through 2.9.3, 2.10.0 through 2.10.4, 3.0.0-alpha.1 through 3.0.0-alpha.4, and 3.0.0-alpha.8 through 3.0.0-alpha.10, as well as `AlastairLundy.CliInvoke.Specializations` versions 1.0.0-rc.1 through 1.6.1.1, contain an OS command injection vulnerability in their PowerShell and Cmd wrappers. The wrappers pass a caller-controlled target and arguments to `pwsh -Command` or `cmd /c` using a single `ProcessStartInfo.Arguments` string, allowing a double quote in untrusted input to break operating-system-level quoting and cause the shell to execute an additional command with the host process's privileges. The vulnerability is patched in `CliInvoke.Specializations` versions 2.8.5, 2.9.4, 2.10.5, and 3.0.0-beta.1, and in `AlastairLundy.CliInvoke.Specializations` version 2.0.2. No complete workaround is available; users unable to upgrade should reject or remove double quotes from target paths and arguments, additionally reject shell metacharacters in versions 2.2.0 through 2.9.2 and 3.0.0-alpha.1 through 3.0.0-alpha.4, or bypass the PowerShell and Cmd wrappers and invoke target processes directly when handling untrusted input.

What this means for your business

  • An attacker can use it only with access to the machine itself, without a login, and without anyone at your company clicking anything.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

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Scoring

CVSS
8.4 (v3.1)
Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-78
Assigned by
security-advisories@github.com

Dates

Published
2026-09-25
Last modified
2026-09-25
Sources
NVD

References