Microsoft Windows SMB Registry : Schedule Key Permission Weakness Local Privilege Escalation

#
# (C) Tenable Network Security, Inc.
#


include("compat.inc");

if (description)
{
 script_id(10426);
 script_version("$Revision: 1.29 $");
 script_cvs_date("$Date: 2015/01/12 17:12:48 $");
 script_cve_id("CVE-1999-0589");

 script_name(english:"Microsoft Windows SMB Registry : Schedule Key Permission Weakness Local Privilege Escalation");
 script_summary(english:"Determines the access rights of a remote key");

 script_set_attribute(attribute:"synopsis", value:"Local users can elevate their privileges.");
 script_set_attribute(attribute:"description", value:
"The registry key SYSTEM\CurrentControlSet\Services\Schedule is
writeable by users who are not in the admin group.

Since the scheduler runs with SYSTEM privileges, this allow a
malicious user to gain these privileges on this system.");
 script_set_attribute(attribute:"solution", value:
"Use regedt32 and set the permissions of this key to :

- admin group  : Full Control
    - system	   : Full Control
    - everyone	   : Read");
 script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");

 script_set_attribute(attribute:"plugin_publication_date", value:"2000/05/29");

script_set_attribute(attribute:"plugin_type", value:"local");
script_end_attributes();

 script_category(ACT_GATHER_INFO);
 script_copyright(english:"This script is Copyright (C) 2000-2015 Tenable Network Security, Inc.");
 script_family(english:"Windows");
 script_dependencies("netbios_name_get.nasl", "smb_login.nasl", "smb_registry_access.nasl");
 script_require_keys("SMB/transport", "SMB/name", "SMB/login", "SMB/password", "SMB/registry_access");
 script_require_ports(139, 445);
 exit(0);
}

include("audit.inc");
include("smb_func.inc");

access = get_kb_item("SMB/registry_access");
if(!access)exit(0, "Registry not accessible.");

login	= kb_smb_login();
pass	= kb_smb_password();
domain  = kb_smb_domain();
port	= kb_smb_transport();

if(! smb_session_init()) audit(AUDIT_FN_FAIL, "smb_session_init");

r = NetUseAdd(login:login, password:pass, domain:domain, share:"IPC$");
if ( r != 1 )
{
 NetUseDel();
 audit(AUDIT_SHARE_FAIL, "IPC$");
}

hklm = RegConnectRegistry(hkey:HKEY_LOCAL_MACHINE);
if ( isnull(hklm) )
{
 NetUseDel();
 audit(AUDIT_REG_FAIL);
}

key = "SYSTEM\CurrentControlSet\Services\Schedule";

key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED | ACCESS_SYSTEM_SECURITY);
if(!isnull(key_h))
{
 rep = RegGetKeySecurity (handle:key_h, type: DACL_SECURITY_INFORMATION | SACL_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION | OWNER_SECURITY_INFORMATION);
 if(!isnull(rep) && registry_key_writeable_by_non_admin(security_descriptor:rep))
 {
   security_hole (port);
 }
 RegCloseKey (handle:key_h);
}

RegCloseKey (handle:hklm);
NetUseDel();