Windows Security Boundaries
When to Activate
- Planning a privilege-escalation path that crosses a Windows security boundary
(integrity level, AppContainer/LPAC, PPL, or the kernel/user line)
- Sandbox-escape research: browser renderer (Chromium/Edge Mojo), Office WebView, packaged
apps, AppContainer/LPAC brokers
- Reaching Ring 0 via win32k/dxgkrnl bugs or BYOVD for a kernel read/write primitive
- Defeating PPL to dump LSASS or tamper with EDR self-defense
- Going from a
SeImpersonate service account to SYSTEM via RPC/ALPC/named-pipe abuse
- UAC bypass (Medium → High) via auto-elevating COM or registry hijack
Boundary stack (high → low): VTL1 (Secure Kernel/Cred Guard) > Ring 0 (ntoskrnl/win32k/drivers) > Ring 3: System > High > Medium > Low > AppContainer/LPAC. PPL is an orthogonal wall guarding LSASS/EDR even from SYSTEM.
Technique Map
| Technique |
ATT&CK |
CWE |
Reference |
Script |
| win32k / dxgkrnl UAF → kernel R/W → token steal |
T1068 |
CWE-416 |
references/kernel-user-boundary.md |
scripts/ioctl_fuzzer.py |
| Driver IOCTL abuse (METHOD_NEITHER arb-R/W) |
T1068 |
CWE-781 |
references/kernel-user-boundary.md |
scripts/ioctl_fuzzer.py |
| BYOVD load + MSR/LSTAR or phys R/W → SYSTEM |
T1068, T1543.003 |
CWE-1188 |
references/byovd-kernel-rw.md |
scripts/byovd_kernel_rw.c |
| BYOVD EDR-kill (callback nulling) |
T1562.001, T1014 |
CWE-1188 |
references/byovd-kernel-rw.md |
scripts/byovd_kernel_rw.c |
| UAC bypass — ICMLuaUtil elevated COM moniker |
T1548.002 |
CWE-269 |
references/integrity-uac-com.md |
scripts/uac_com_elevate.cpp |
| UAC bypass — fodhelper HKCU registry hijack |
T1548.002, T1112 |
CWE-269 |
references/integrity-uac-com.md |
scripts/uac_com_elevate.cpp |
| AppContainer/LPAC broker abuse / cap over-grant |
T1211 |
CWE-668 |
references/sandbox-appcontainer-escape.md |
scripts/sandbox_escape_probe.py |
| Chromium/Edge Mojo IPC sandbox escape |
T1211 |
CWE-501 |
references/sandbox-appcontainer-escape.md |
scripts/sandbox_escape_probe.py |
| Named-object / symbolic-link squatting |
T1211 |
CWE-59 |
references/sandbox-appcontainer-escape.md |
scripts/sandbox_escape_probe.py |
| PPL bypass — BYOVDLL (old signed DLL into PPL) |
T1003.001, T1211 |
CWE-426 |
references/ppl-protected-process.md |
scripts/ppl_byovdll.c |
| PPL bypass — live-dump / WER / Protection-clear |
T1003.001, T1562.001 |
CWE-269 |
references/ppl-protected-process.md |
scripts/byovd_kernel_rw.c |
| RPC server spoof / endpoint squat (PhantomRPC) |
T1559, T1134.001 |
CWE-287 |
references/rpc-alpc-boundary.md |
scripts/named_pipe_impersonate.c |
| Named-pipe client impersonation (Potato family) |
T1134.002, T1134.001 |
CWE-294 |
references/rpc-alpc-boundary.md |
scripts/named_pipe_impersonate.c |
| Host boundary posture enumeration |
T1082 |
CWE-693 |
(all) |
scripts/enum_boundaries.ps1 |
Quick Start
:: 0. Map the host's boundary posture -> pick the right primitive
powershell -ep bypass -File scripts/enum_boundaries.ps1
:: reports: integrity, AppContainer, SeImpersonate/SeDebug, HVCI, driver blocklist,
:: LSASS RunAsPPL, drivers loaded from user-writable paths, named-pipe count.
:: 1. From a sandbox (renderer/packaged app): rank escape vectors
python scripts/sandbox_escape_probe.py
:: 2. Medium -> High: UAC bypass (no file dropped via COM moniker)
uac_com_elevate.exe com "C:\Windows\System32\cmd.exe /c whoami /groups > C:\poc.txt"
:: 3. SeImpersonate present -> SYSTEM via PhantomRPC endpoint squat
whoami /priv | findstr SeImpersonate
named_pipe_impersonate.exe \\.\pipe\W32TIME "C:\Windows\System32\cmd.exe"
w32tm /resync :: triggers the SYSTEM client to connect
:: 4. Need Ring 0: map a driver's IOCTLs, then BYOVD kernel R/W -> token steal
python scripts/ioctl_fuzzer.py --device RTCore64 --map
byovd_kernel_rw.exe C:\test\driver.sys token
:: 5. Dump LSASS under PPL without a driver (BYOVDLL / CNG KSP)
ppl_byovdll.exe register C:\stage\vuln_ncryptprov.dll GhostKsp
ppl_byovdll.exe trigger GhostKsp
OPSEC & Detection (summary)
| Technique |
Telemetry / IOC |
Detection (Sigma / EDR) |
OPSEC note |
| win32k/dxgkrnl exploit |
Bugcheck EID 1001 ref win32k/dxgkrnl; process token flips to S-1-5-18 with no service genealogy |
Sigma on bugchecks + token anomaly; ETW Microsoft-Windows-Win32k |
Prefer data-only token copy over CFG/CET-fighting control-flow hijack; missed race = loud bugcheck |
| BYOVD |
Sysmon EID 6 driver load from user-writable path; 7045/4697 kernel service; EDR telemetry goes silent |
Sigma on unusual driver path + known-bad hashes (loldrivers.io); driver-load-time window |
Use un-blocklisted/HVCI-compatible driver; restore LSTAR/callbacks; DeleteService + del .sys |
| UAC bypass (COM/fodhelper) |
Sysmon EID 13 write to HKCU ms-settings\Shell\Open\command; dllhost /Processid:{3E5FC7F9..} spawning shell |
Elastic/ManageEngine ICMLuaUtil + fodhelper rules |
Rotate to a less-known AutoElevate CLSID; don't spawn cmd from dllhost; clean HKCU tree |
| Sandbox escape |
Renderer/GPU process spawning cmd/powershell/rundll32; Mojo handle-transfer anomalies |
Sigma on browser child-process; patch-posture alert (Edge<134.0.3124.93) |
Stay in-process post-escape (IPC layer is an EDR blind spot); symlink squat is mostly dead post-2017 |
| PPL bypass |
Old keyiso/ncryptprov version loaded in lsass (EID 7); EID 10 lsass read; Cryptography\Providers write; live-dump |
Sigma on DLL version-mismatch + GrantedAccess to lsass |
Driverless (BYOVDLL/WER/live-dump) avoids BYOVD noise; restore Protection byte; obfuscate dumps |
| RPC/ALPC impersonation |
4624 logon type 9 (Advapi); SYSTEM child of service-acct parent; RPC_S_SERVER_UNAVAILABLE (EID 1) |
Elastic named-pipe impersonation rule; ETW RPC + high impersonation level |
PhantomRPC endpoint squat blends w/ admin triggers (w32tm/gpupdate); RevertToSelf + close pipe |
Deep Dives
- references/kernel-user-boundary.md — Ring 3→Ring 0 via win32k/dxgkrnl UAF
(CVE-2025-24983, CVE-2025-62573, CVE-2025-55224, CVE-2025-62221, CVE-2026-26132), driver
IOCTL surface, kernel R/W → EPROCESS token steal / Protection clear / PreviousMode, modern
no-PTE-self-map constraint, KDP/HVCI considerations.
- references/byovd-kernel-rw.md — Bring-Your-Own-Vulnerable-Driver: load signed driver,
MSR-LSTAR vs physical-memory primitives (CVE-2025-8061), EDRKillShifter / Qilin driver
rotation, 2025-2026 driver+CVE catalog, blocklist/HVCI bypass, driver-load detection.
- references/integrity-uac-com.md — integrity model, appinfo/autoElevate internals,
fodhelper (UACME 33) + ICMLuaUtil/CMSTPLUA (UACME 41), 2025 IEditionUpgradeManager bypass,
finding new AutoElevate COM classes, T1548.002 ITW campaigns.
- references/sandbox-appcontainer-escape.md — AppContainer/LPAC model + capabilities,
broker abuse (WinRT XmlDocument), Chromium/Edge Mojo escapes (CVE-2025-2783 ForumTroll,
CVE-2025-4609 ipcz), symbolic-link/RtlIsSandboxToken mitigation, 3-bug renderer chain.
- references/ppl-protected-process.md — PS_PROTECTION/signer levels, BYOVDLL "Ghost in
the PPL" (CVE-2023-28229/36906, BCryptRegisterProvider), NtSystemDebugControl live-dump
(Win11 23H2), WER dump, kernel Protection-clear, PPLBlade, Credential Guard hard stop.
- references/rpc-alpc-boundary.md — named-pipe client impersonation primitive, ALPC
SQoS/RequiredServerSid, PhantomRPC server-spoof/endpoint-squat (2026, unpatched), Potato
family (PrintSpoofer/GodPotato/SigmaPotato), WER ALPC LPE, NtObjectManager enumeration.