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4705(S): A user right was removed.

Event 4705 illustration

Subcategory: Audit Authorization Policy Change

Event Description:

This event generates every time local user right policy is changed and user right was removed from an account.

You will see unique event for every user.

Note  For recommendations, see Security Monitoring Recommendations for this event.


Event XML:

- <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
 <Provider Name="Microsoft-Windows-Security-Auditing" Guid="{54849625-5478-4994-A5BA-3E3B0328C30D}" /> 
 <EventID>4705</EventID> 
 <Version>0</Version> 
 <Level>0</Level> 
 <Task>13570</Task> 
 <Opcode>0</Opcode> 
 <Keywords>0x8020000000000000</Keywords> 
 <TimeCreated SystemTime="2015-10-02T22:08:07.152488600Z" /> 
 <EventRecordID>1049867</EventRecordID> 
 <Correlation /> 
 <Execution ProcessID="500" ThreadID="1216" /> 
 <Channel>Security</Channel> 
 <Computer>DC01.contoso.local</Computer> 
 <Security /> 
 </System>
- <EventData>
 <Data Name="SubjectUserSid">S-1-5-18</Data> 
 <Data Name="SubjectUserName">DC01$</Data> 
 <Data Name="SubjectDomainName">CONTOSO</Data> 
 <Data Name="SubjectLogonId">0x3e7</Data> 
 <Data Name="TargetSid">S-1-5-21-3457937927-2839227994-823803824-1104</Data> 
 <Data Name="PrivilegeList">SeTimeZonePrivilege</Data> 
 </EventData>
 </Event>

Required Server Roles: None.

Minimum OS Version: Windows Server 2008, Windows Vista.

Event Versions: 0.

Field Descriptions:

Subject:

  • Security ID [Type = SID]: SID of account that made a change to local user right policy. Event Viewer automatically tries to resolve SIDs and show the account name. If the SID cannot be resolved, you will see the source data in the event.

Note  A security identifier (SID) is a unique value of variable length used to identify a trustee (security principal). Each account has a unique SID that is issued by an authority, such as an Active Directory domain controller, and stored in a security database. Each time a user logs on, the system retrieves the SID for that user from the database and places it in the access token for that user. The system uses the SID in the access token to identify the user in all subsequent interactions with Windows security. When a SID has been used as the unique identifier for a user or group, it cannot ever be used again to identify another user or group. For more information about SIDs, see Security identifiers.

  • Account Name [Type = UnicodeString]: the name of the account that made a change to local user right policy.

  • Account Domain [Type = UnicodeString]: subject’s domain or computer name. Formats vary, and include the following:

    • Domain NETBIOS name example: CONTOSO

    • Lowercase full domain name: contoso.local

    • Uppercase full domain name: CONTOSO.LOCAL

    • For some well-known security principals, such as LOCAL SERVICE or ANONYMOUS LOGON, the value of this field is “NT AUTHORITY”.

    • For local user accounts, this field will contain the name of the computer or device that this account belongs to, for example: “Win81”.

  • Logon ID [Type = HexInt64]: hexadecimal value that can help you correlate this event with recent events that might contain the same Logon ID, for example, “4624: An account was successfully logged on.”

Target Account:

  • Account Name [Type = SID]: the SID of security principal for which user rights were removed. Event Viewer automatically tries to resolve SIDs and show the account name. If the SID cannot be resolved, you will see the source data in the event.

Removed Right:

  • User Right [Type = UnicodeString]: the list of removed user rights. This event generates only for user rights, not logon rights. Here is the list of possible user rights:
Privilege Name User Right Group Policy Name Description
SeAssignPrimaryTokenPrivilege Replace a process-level token Required to assign the primary token of a process.
With this privilege, the user can initiate a process to replace the default token associated with a started subprocess.
SeAuditPrivilege Generate security audits With this privilege, the user can add entries to the security log.
SeBackupPrivilege Back up files and directories - Required to perform backup operations.
With this privilege, the user can bypass file and directory, registry, and other persistent object permissions for the purposes of backing up the system.
This privilege causes the system to grant all read access control to any file, regardless of the access control list (ACL) specified for the file. Any access request other than read is still evaluated with the ACL. The following access rights are granted if this privilege is held:
READ_CONTROL
ACCESS_SYSTEM_SECURITY
FILE_GENERIC_READ
FILE_TRAVERSE
SeChangeNotifyPrivilege Bypass traverse checking Required to receive notifications of changes to files or directories. This privilege also causes the system to skip all traversal access checks.
With this privilege, the user can traverse directory trees even though the user may not have permissions on the traversed directory. This privilege does not allow the user to list the contents of a directory, only to traverse directories.
SeCreateGlobalPrivilege Create global objects Required to create named file mapping objects in the global namespace during Terminal Services sessions.
SeCreatePagefilePrivilege Create a pagefile With this privilege, the user can create and change the size of a pagefile.
SeCreatePermanentPrivilege Create permanent shared objects Required to create a permanent object.
This privilege is useful to kernel-mode components that extend the object namespace. Components that are running in kernel mode already have this privilege inherently; it is not necessary to assign them the privilege.
SeCreateSymbolicLinkPrivilege Create symbolic links Required to create a symbolic link.
SeCreateTokenPrivilege Create a token object Allows a process to create a token which it can then use to get access to any local resources when the process uses NtCreateToken() or other token-creation APIs.
When a process requires this privilege, we recommend using the LocalSystem account (which already includes the privilege), rather than creating a separate user account and assigning this privilege to it.
SeDebugPrivilege Debug programs Required to debug and adjust the memory of a process owned by another account.
With this privilege, the user can attach a debugger to any process or to the kernel. Developers who are debugging their own applications do not need this user right. Developers who are debugging new system components need this user right. This user right provides complete access to sensitive and critical operating system components.
SeEnableDelegationPrivilege Enable computer and user accounts to be trusted for delegation Required to mark user and computer accounts as trusted for delegation.
With this privilege, the user can set the Trusted for Delegation setting on a user or computer object.
The user or object that is granted this privilege must have write access to the account control flags on the user or computer object. A server process running on a computer (or under a user context) that is trusted for delegation can access resources on another computer using the delegated credentials of a client, as long as the account of the client does not have the Account cannot be delegated account control flag set.
SeImpersonatePrivilege Impersonate a client after authentication With this privilege, the user can impersonate other accounts.
SeIncreaseBasePriorityPrivilege Increase scheduling priority Required to increase the base priority of a process.
With this privilege, the user can use a process with Write property access to another process to increase the execution priority assigned to the other process. A user with this privilege can change the scheduling priority of a process through the Task Manager user interface.
SeIncreaseQuotaPrivilege Adjust memory quotas for a process Required to increase the quota assigned to a process.
With this privilege, the user can change the maximum memory that can be consumed by a process.
SeIncreaseWorkingSetPrivilege Increase a process working set Required to allocate more memory for applications that run in the context of users.
SeLoadDriverPrivilege Load and unload device drivers Required to load or unload a device driver.
With this privilege, the user can dynamically load and unload device drivers or other code in to kernel mode. This user right does not apply to Plug and Play device drivers.
SeLockMemoryPrivilege Lock pages in memory Required to lock physical pages in memory.
With this privilege, the user can use a process to keep data in physical memory, which prevents the system from paging the data to virtual memory on disk. Exercising this privilege could significantly affect system performance by decreasing the amount of available random access memory (RAM).
SeMachineAccountPrivilege Add workstations to domain With this privilege, the user can create a computer account.
This privilege is valid only on domain controllers.
SeManageVolumePrivilege Perform volume maintenance tasks Required to run maintenance tasks on a volume, such as remote defragmentation.
SeProfileSingleProcessPrivilege Profile single process Required to gather profiling information for a single process.
With this privilege, the user can use performance monitoring tools to monitor the performance of non-system processes.
SeRelabelPrivilege Modify an object label Required to modify the mandatory integrity level of an object.
SeRemoteShutdownPrivilege Force shutdown from a remote system Required to shut down a system using a network request.
SeRestorePrivilege Restore files and directories Required to perform restore operations. This privilege causes the system to grant all write access control to any file, regardless of the ACL specified for the file. Any access request other than write is still evaluated with the ACL. Additionally, this privilege enables you to set any valid user or group SID as the owner of a file. The following access rights are granted if this privilege is held:
WRITE_DAC
WRITE_OWNER
ACCESS_SYSTEM_SECURITY
FILE_GENERIC_WRITE
FILE_ADD_FILE
FILE_ADD_SUBDIRECTORY
DELETE
With this privilege, the user can bypass file, directory, registry, and other persistent objects permissions when restoring backed up files and directories and determines which users can set any valid security principal as the owner of an object.
SeSecurityPrivilege Manage auditing and security log Required to perform a number of security-related functions, such as controlling and viewing audit events in security event log.
With this privilege, the user can specify object access auditing options for individual resources, such as files, Active Directory objects, and registry keys.
A user with this privilege can also view and clear the security log.
SeShutdownPrivilege Shut down the system Required to shut down a local system.
SeSyncAgentPrivilege Synchronize directory service data This privilege enables the holder to read all objects and properties in the directory, regardless of the protection on the objects and properties. By default, it is assigned to the Administrator and LocalSystem accounts on domain controllers.
With this privilege, the user can synchronize all directory service data. This is also known as Active Directory synchronization.
SeSystemEnvironmentPrivilege Modify firmware environment values Required to modify the nonvolatile RAM of systems that use this type of memory to store configuration information.
SeSystemProfilePrivilege Profile system performance Required to gather profiling information for the entire system.
With this privilege, the user can use performance monitoring tools to monitor the performance of system processes.
SeSystemtimePrivilege Change the system time Required to modify the system time.
With this privilege, the user can change the time and date on the internal clock of the computer. Users that are assigned this user right can affect the appearance of event logs. If the system time is changed, events that are logged will reflect this new time, not the actual time that the events occurred.
SeTakeOwnershipPrivilege Take ownership of files or other objects Required to take ownership of an object without being granted discretionary access. This privilege allows the owner value to be set only to those values that the holder may legitimately assign as the owner of an object.
With this privilege, the user can take ownership of any securable object in the system, including Active Directory objects, files and folders, printers, registry keys, processes, and threads.
SeTcbPrivilege Act as part of the operating system This privilege identifies its holder as part of the trusted computer base.
This user right allows a process to impersonate any user without authentication. The process can therefore gain access to the same local resources as that user.
SeTimeZonePrivilege Change the time zone Required to adjust the time zone associated with the computer's internal clock.
SeTrustedCredManAccessPrivilege Access Credential Manager as a trusted caller Required to access Credential Manager as a trusted caller.
SeUndockPrivilege Remove computer from docking station Required to undock a laptop.
With this privilege, the user can undock a portable computer from its docking station without logging on.
SeUnsolicitedInputPrivilege Not applicable Required to read unsolicited input from a terminal device.

Security Monitoring Recommendations

For 4705(S): A user right was removed.

Type of monitoring required Recommendation
Actions typically performed by the SYSTEM account: This event and certain other events should be monitored to see if they are triggered by any account other than SYSTEM. Because this event is typically triggered by the SYSTEM account, we recommend that you report it whenever “Subject\Security ID” is not SYSTEM.
High-value accounts: You might have high-value domain or local accounts for which you need to monitor each action.
Examples of high-value accounts are database administrators, built-in local administrator account, domain administrators, service accounts, domain controller accounts and so on.
Monitor this event with the “Subject\Security ID” that corresponds to the high-value account or accounts.
Anomalies or malicious actions: You might have specific requirements for detecting anomalies or monitoring potential malicious actions. For example, you might need to monitor for use of an account outside of working hours. When you monitor for anomalies or malicious actions, use the “Subject\Security ID” (with other information) to monitor how or when a particular account is being used.
Non-active accounts: You might have non-active, disabled, or guest accounts, or other accounts that should never be used. Monitor this event with the “Subject\Security ID” or “Target Account\Account Name” that correspond to the accounts that should never be used.
Account allowlist: You might have a specific allowlist of accounts that are the only ones allowed to perform actions corresponding to particular events. If this event corresponds to an “allowlist-only” action, review the “Subject\Security ID” for accounts that are outside the allowlist.
If you have specific user rights policies, for example, an allowlist of accounts that can perform certain actions, monitor this event to confirm that it was appropriate that the “Removed Right” was removed from “Target Account\Account Name.”
Accounts of different types: You might want to ensure that certain actions are performed only by certain account types, for example, local or domain account, machine or user account, vendor or employee account, and so on. If this event corresponds to an action you want to monitor for certain account types, review the “Subject\Security ID” and “Target Account\Account Name” to see whether the account type is as expected.
For example, if some accounts have critical user rights which should never be removed, monitor this event for the “Target Account\Account Name” and the appropriate rights.
As another example, if non-administrative accounts should never be granted certain user rights (for example, SeAuditPrivilege), you might monitor this event, because a right can be removed only after it was previously granted.
External accounts: You might be monitoring accounts from another domain, or “external” accounts that are not allowed to perform certain actions (represented by certain specific events). Monitor this event for the “Subject\Account Domain” corresponding to accounts from another domain or “external” accounts.
Restricted-use computers or devices: You might have certain computers, machines, or devices on which certain people (accounts) should perform only limited actions, or no actions at all. Monitor the target Computer: (or other target device) for actions performed by the “Subject\Security ID” that you are concerned about. Also be sure to check “Target Account\Account Name” to see whether user rights should be removed from that account (or whether that account should have any rights on that computer).
For high-value servers or other computers, we recommend that you track this event and investigate whether the specific “Removed Right” should be removed from “Target Account\Account Name” in each case.
User rights that should be restricted: You might have a list of user rights that you want to monitor. Monitor this event and compare the “Removed Right” to your list of restricted rights.
Monitor this event to discover the removal of a right that should never have been granted (for example, SeTcbPrivilege), so that you can investigate further.
Account naming conventions: Your organization might have specific naming conventions for account names. Monitor “Subject\Account Name” for names that don’t comply with naming conventions.