Findings of a Claude security scan against b4af8c7, each measured first, plus
the MSI channel incident a parallel session found.
- Installer 2.8 extracts the agent ZIP with its own containment check
(Expand-AgentPayload): every entry is resolved against the payload folder
before the first write, a rooted or escaping name refuses the package. The
inbox Expand-Archive of Windows PowerShell 5.1 already refuses such entries
(measured), so the finding was not exploitable as reported; the guarantee is
now the script's own, pinned by tests, and Expand-Archive is banned.
- Installer 2.8 also moves PowerShell's own location out of the agent folder
(Set-Location): on the MSI channel the location pointed at the deleted Msi
folder and the agent start failed with error 267 since 2.7 went live. When
the agent program never started, the Agent folder is removed again so a later
run can install; the stderr line is flattened to one line.
- Run folders younger than an hour stay (a loader may still run there); the
loader's log is taken only from a run folder that is ours.
- Loader 1.4 (minimum installer 2.8) checks before every download attempt that
its run folder is still a real folder of ours, opens the download for reading
before the signature and identity checks and holds it until the run ends, so
what it checked is what runs and nothing can replace or delete it meanwhile.
- Agent: the protected folder security names Administrators as owner; a folder
with another owner or a reparse point is not taken as protected, reparse points
are refused, the base is created protected, install mode protects base and
Agent and refuses to install when it cannot; every start re-checks both.
- Bootstrap MSI 1.3.0 installs its loader under Program Files, where a standard
user cannot create the folder first.
- Tests: containment table, hour rule, held handle, owner and junction tests
(ElevatedFact for the owner assignment), MSI location contract; harness
scenarios for an escaping package (installer and OOBE script), the hour rule,
the Program Files layout and an agent that does not start, with the install
stand-in starting a real program from PowerShell's location. OOBE golden
regenerated.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
- Loader 1.3 downloads into a protected run folder of its own
(%ProgramData%\AutopilotMonitor-Loader-<8 hex>), runs the installer only when it
is signed by the pinned publisher and declares the installer role and version
2.7 or later, removes the folder after a successful run and never touches the
agent folder. Unbound arguments now reach the installer by name; the array
splat bound them by position.
- Installer 2.7 refuses without elevation and decides before it writes: guards
read HKLM through the 64-bit view (a 32-bit host never saw the deployment
marker), guard 5 is covered by the agent check. An agent's folder stays as it
is, a skip without agent removes the folder, an install starts from an emptied,
protected folder and stages the ZIP in a run folder. It moves the MSI's working
directory out, writes stderr only on failure and removes the copy older loaders
left at the fixed path.
- Help texts of both scripts state what customers need; .CHANGELOG, which made
Get-Help ignore the help, gives way to the Platform Changelog.
- OOBE go-script: the installer's shared helpers, its own elevation check
(#Requires is ignored under irm | iex), a run folder.
- Publish: version read line-anchored, the loader's own check on the exact
publish bytes, installers before loaders, -Channel dev (dispatch input).
- Bootstrap MSI 1.2.0; Test-ShouldBootstrapAgent reads the 64-bit view;
Uninstall removes loader run folders and keeps the Deployed marker.
- Tests: Pester unit suites, an integration harness running the real scripts
(loader 1.2 and the MSI 1.0 runner frozen in TestData), BootstrapContractTests;
the gate runs on windows-2022 and windows-2025, once more as SYSTEM, and against
a real standard user.
[skip actions]: published by a dispatch of publish-scripts.yml, channel dev first.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- Install-AutopilotMonitor.ps1 v2.6: Get-AgentPayloadRejections (Test-FileCatalog
-Detailed; signature Valid, signer -like the pin, files exactly as catalogued) and
Install-VerifiedAgentPayload (extract into Agent-Install, verify there, then move into
the agent folder; a rejection deletes the staging folder, so the next run starts clean).
Replaces the name-filtered Get-UnverifiedAgentBinaries; the dead "already installed"
branch behind guard 5 is gone.
- OOBE go-script: embeds the installer's marked block verbatim (EmbeddedResource) and
verifies before --install; pin and catalog name come from the Shared constants; the
golden is updated, new tests pin the embedding and the order check-before-install.
- build-agent.yml: the release verify step dot-sources the installer and runs its own
function on the final ZIP.
- Pester: every decision branch, a real unsigned catalog, the staging flow (64/64).
- Privacy page: the catalog claim; LAST_UPDATED.
Merge only after a catalog ZIP is live on stable (plan step V0): pushing this to main
publishes the installer to every loader on its next run.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The SHA-256 check proves the ZIP is the one version.json names, but that
manifest lives in the same container as the ZIP: it cannot outlive a
compromise of the download host. The expected publisher travels inside this
script, which the loader verified before running it, so the chain from the
file an administrator assigns to the process that starts is publisher-anchored
end to end.
Install-AutopilotMonitor.ps1 v2.4 -> v2.5:
- Get-UnverifiedAgentBinaries checks every AutopilotMonitor.*.exe/.dll in the
extracted payload for status Valid and the same subject pin the loader
carries; the gate runs immediately before --install and throws on any
rejection, exactly like the hash check.
- Third-party assemblies keep their own publisher's signature and are not
checked: System.Management.Automation.dll ships unsigned, so a gate over all
files would refuse the live payload.
- An extracted folder with no binary of ours is a rejection, not a pass.
- The SHA-256 manifest check is unchanged and still runs first: it proves the
bytes, the signature proves the author.
Verified against the live payload 2.0.1454 (all five of our PEs Valid and
glueckkanja AG, gate passes); appending one byte to AutopilotMonitor.Shared.dll
makes it reject. Pester 55/55.
The portal privacy and about pages carried the pre-signing wording and are
corrected in the same change.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Install-AutopilotMonitor.ps1 takes over the field-tested v2.3-dev.3 logic
unchanged (code-only diff vs dev: ScriptVersion + log file name); comments
condensed to customer-facing descriptions, dev changelog collapsed into one
v2.3 entry. Pester suite moved to Install-AutopilotMonitor.Tests.ps1 (neutral
test user names), dev script and dev suite removed. Test-ShouldBootstrapAgent
dry-run tester mirrors the Cloud PC trigger and the guard-4 uptime exemption.
Pester 29/29 green under PS 5.1 and pwsh 7; parse + pure-ASCII checks pass.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Oliver Kieselbach