Access denied to a memory section from a Windhawk mod

[Anixx]

I have the following mod:

// ==WindhawkMod==
// @id              classic-theme-enable
// @name            Enable Classic Theme [WinClassic modeset]
// @description     Disables theming by closing the handle
// @version         0.1
// @author          Anixx
// @include         winlogon.exe
// @compilerOptions -lntdll
// ==/WindhawkMod==

#include <iostream>
#include <sddl.h>
#include <winnt.h>
#include <winternl.h>
#include <aclapi.h>
#include <securitybaseapi.h>

// Define the prototype for the NtOpenSection function.
extern "C" NTSTATUS NTAPI NtOpenSection(
    OUT PHANDLE SectionHandle,
    IN ACCESS_MASK DesiredAccess,
    IN POBJECT_ATTRIBUTES ObjectAttributes
);

BOOL Wh_ModInit() {

    Wh_Log(L"Init");

    // Retrieve the current session ID for the process.
    DWORD sessionId;
    if (!ProcessIdToSessionId(GetCurrentProcessId(), &sessionId)) {
        return 1;
    }

    wchar_t sectionName[256];
    swprintf_s(sectionName, _countof(sectionName), L"\\Sessions\\%lu\\Windows\\ThemeSection", sessionId);

    // Define the name of the section object.
    UNICODE_STRING sectionObjectName;
    RtlInitUnicodeString(&sectionObjectName, sectionName);

    // Define the attributes for the section object.
    OBJECT_ATTRIBUTES objectAttributes;
    InitializeObjectAttributes(&objectAttributes, &sectionObjectName, OBJ_CASE_INSENSITIVE, NULL, NULL);

    HANDLE hSection;
    NTSTATUS status = NtOpenSection(&hSection, WRITE_DAC, &objectAttributes);

    Wh_Log("status: %u\n", status);
    Wh_Log("%s", sectionName);

    // Define your SDDL string.
    LPCWSTR sddl = L"O:BAG:SYD:(A;;RC;;;IU)(A;;DCSWRPSDRCWDWO;;;SY)";
    PSECURITY_DESCRIPTOR psd = NULL;

    // Convert the SDDL string to a security descriptor.
    if (!ConvertStringSecurityDescriptorToSecurityDescriptorW(sddl, SDDL_REVISION_1, &psd, NULL)) {
        CloseHandle(hSection);
        return 1;
    }

     // Set the security descriptor for the object.
    BOOL result = SetKernelObjectSecurity(
        hSection,
        DACL_SECURITY_INFORMATION,
        psd
    );

        Wh_Log("result: %u\n", result);

    // Cleanup: free allocated security descriptor memory and close the handle.
    LocalFree(psd);
    CloseHandle(hSection);

    return result;
}

// The mod is being unloaded, free all allocated resources.
void Wh_ModUninit() {
    Wh_Log(L"Uninit");
}

It works only when injected into Winlogon.exe but not any other process with system or admin rights. How to fix this?