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01-1. How do I access the password file in Novell Netware?
01-2. How do I crack Novell Netware passwords?
01-3. What are common accounts and passwords in Novell Netware?
01-4. How can I figure out valid account names on Novell Netware?
01-5. What is the "secret" method to gain Supervisor access Novell used to teach in CNE classes?
01-6. What is the cheesy way to get Supervisor access?
01-7. How do I leave a backdoor?
01-8. Can sniffing packets help me break in?
01-9. What is Packet Signature and how do I get around it?
01-10. How do I use SETPWD.NLM?
01-11. What's the "debug" way to disable passwords?
Section 01
Contrary to not-so-popular belief, access to the password file in Netware is not like Unix - the password file isn't in the open. All objects and their properties are kept in the bindery files on 2.x and 3.x, and kept in the NDS database in 4.x. An example of an object might be a printer, a group, an individual's account etc. An example of an object's properties might include an account's password or full user name, or a group's member list or full name. The bindery files attributes (or flags) in 2.x and 3.x are Hidden and System, and these files are located on the SYS: volume in the SYSTEM subdirectory. Their names are as follows:
Netware version File Names --------------- ---------- 2.x NET$BIND.SYS, NET$BVAL.SYS 3.x NET$OBJ.SYS, NET$PROP.SYS, NET$VAL.SYS
The NET$BVAL.SYS and NET$VAL.SYS are where the passwords are actually located in 2.x and 3.x respectively.
In Netware 4.x, the files are physically located in a different location than on the SYS: volume. However, by using the RCONSOLE utility and using the Scan Directory option, you can see the files in SYS:_NETWARE:
File What it is -------------- -------------------------- VALUE.NDS Part of NDS BLOCK.NDS Part of NDS ENTRY.NDS Part of NDS PARTITIO.NDS Type of NDS partition (replica, master, etc.) MLS.000 License VALLINCEN.DAT License validation
Here is another way to view these files, and potentially edit them. After installing NW4 on a NW3 volume, reboot the server with a 3.x SERVER.EXE. On volume SYS will be the _NETWARE directory. SYS:_NETWARE is hidden better on 4.1 than 4.0x, but in 4.1 you can still see the files by scanning directory entry numbers using NCP calls (you need the APIs for this) using function 0x17 subfunction 0xF3.
There are a few ways to approach this. First, we'll assume Intruder Detection is turned off. We'll also assume unencrypted passwords are allowed. Hopefully you won't have to deal with packet signature (see 01-9 below) Then we'll assume you have access to the console. Finally we'll assume you can plant some kind of password catcher. Access to a sniffer might help. These are a lot of ifs.
If Intruder Detection is off, you can just guess the password until you get it. This can be automated by writing a program that continually guesses passwords, or by using a program that does just that. One program that I am aware of is NOVELBFH.EXE (for version 3.x only). This program will try passwords like aa, ab, ac and so on until every legal character combination has been tried. You will eventually get the password. However this assumes you have 1) a lot of time since it takes a second or two for each try (more on a dial-up link), and 2) access to a machine that will run one of these programs for hours, even days. And if Intruder Detection is on you will be beeping the System Console every couple of seconds and time-stamping your node address to the File Server Error Log.
Encrypted passwords is Novell's way of protecting passwords from sniffers. Since older versions of Netware (2.15c) sent passwords as plain text over the wire, a sniffer could see the password as it went by. To secure things, Novell gave the administrator a way to control this. Later versions of the LOGIN.EXE program would encrypt the password before transmitting it across the wire to the server. But before this could happen, the shell (NETX) had to be updated. Since some locations had to have older shells and older versions of LOGIN.EXE to support older equipment, the administrator has the option of allowing unencrypted passwords to access the server. This is done by typing SET ALLOW UNENCRYPTED PASSWORDS=ON at the console or by adding it to the AUTOEXEC.NCF. The default is OFF, which means NOVELBFH could be beeping the server console every attempt! Fortunately most sites turn this switch on to support some old device.
If you have access to the console, either by standing in front of it or by RCONSOLE, you can use SETSPASS.NLM, SETSPWD.NLM or SETPWD.NLM to reset passwords. Just load the NLM and pass it command line parameters:
NLM Account(s) reset Netware version(s) supported ------------ ----------------- ---------------------------- SETSPASS.NLM SUPERVISOR 3.x SETSPWD.NLM SUPERVISOR 3.x, 4.x SETPWD.NLM any valid account 3.x, 4.x
See 01-10 for more SETPWD.NLM info.
If you can plant a password catcher or keystroke reader, you can get them this way. The LOGIN.EXE file is located in the SYS:LOGIN directory, and normally you will not have access to put a file in that directory. The best place to put a keystroke capture program is in the workstation's path, with the ATTRIB set as hidden. The advantage is that you'll get the password and Netware won't know you swiped it. The disadvantage is getting access to the machine to do this. The very best place to put one of these capture programs is on a common machine, like a pcAnywhere box, which is used for remote access. Many locations will allow pcAnywhere access to a machine with virtually no software on it, and control security access to the LAN by using Netware's security features. Uploading a keystroke capture program to a machine like this defeats this.
If the system is being backed up via a workstation, this can be used as a good entry point. These workstations have to have supe equiv to back up the bindery and other system files. If you can access this workstation or use the backup systems user account name then you can get supe level login.
itsme, the notorious Netherlands Netware hacker, developed KNOCK.EXE by rewriting one byte of ATTACH.EXE to try without a password to get into a server. KNOCK.EXE utilitzes a bug that allows a non-password attach to get in. This works on versions of Netware earlier than 2.2, and 3.11. Later versions have the bug fixed. Given enough time you will get in.
Another alternative is the replacement LOGIN.EXE by itsme. This jewel, coupled with PROP.EXE, will create a separate property in the bindery on a 2.x or 3.x server that contains the passwords. Here is the steps to use these powerful tools:
Out of the box Novell Netware has the following default accounts - SUPERVISOR, GUEST, and Netware 4.x has ADMIN and USER_TEMPLATE as well. All of these have no password to start with. Virtually every installer quickly gives SUPERVISOR and ADMIN a password. However, many locations will create special purpose accounts that have easy-to-guess names, some with no passwords. Here are a few and their typical purposes:
Account Purpose
---------- ------------------------------------------------------
PRINT Attaching to a second server for printing
LASER Attaching to a second server for printing
HPLASER Attaching to a second server for printing
PRINTER Attaching to a second server for printing
LASERWRITER Attaching to a second server for printing
POST Attaching to a second server for email
MAIL Attaching to a second server for email
GATEWAY Attaching a gateway machine to the server
GATE Attaching a gateway machine to the server
ROUTER Attaching an email router to the server
BACKUP May have password/station restrictions (see below), used
for backing up the server to a tape unit attached to a
workstation. For complete backups, Supervisor equivalence
is required.
WANGTEK See BACKUP
FAX Attaching a dedicated fax modem unit to the network
FAXUSER Attaching a dedicated fax modem unit to the network
FAXWORKS Attaching a dedicated fax modem unit to the network
TEST A test user account for temp use
This should give you an idea of accounts to try if you have access to a machine that attaches to the server. A way to "hide" yourself is to give GUEST or USER_TEMPLATE a password. Occassionally admins will check up on GUEST, but most forget about USER_TEMPLATE. In fact, I forgot about USER_TEMPLATE until itsme reminded me.
A common mistake regarding RCONSOLE passwords is to use a switch to use only the Supervisor password. It works like this:
LOAD REMOTE /P=
instead of
LOAD REMOTE RCONPASSWORD
The admin believes /P= turns off everything except the Supe password for CONSOLE. In fact the password is just set to /P= which will get you in! The second most common mistake is using -S.
Any limited account should have enough access to allow you to run SYSCON, located in the SYS:PUBLIC directory. If you get in, type SYSCON and enter. Now go to User Information and you will see a list of all defined accounts. You will not get much info with a limited account, but you can get the account and the user's full name.
If you're in with any valid account, you can run USERLST.EXE and get a list of all valid account names on the server. If you don't have access (maybe the sys admin deleted the GUEST account, a fairly common practice), you can't just try any account name at the LOGIN prompt. It will ask you for a password whether the account name is valid or not, and if it is valid and you guees the wrong password, you could be letting the world know what you're up to if Intruder Detection is on. But there is a way to determine if an account is valid.
From a DOS prompt use a local copy (on your handy floppy you carry everywhere) of MAP.EXE. After you've loaded the Netware TSRs up through NETX or VLM, Try to map a drive using the server name and volume SYS:. For example:
MAP G:=TARGET_SERVER/SYS:APPS <enter>
Since you are not logged in, you will be prompted for a login ID. If it is a valid ID, you will be prompted for a password. If not, you will immediately receive an error. Of course, if there is no password for the ID you use you will be attached and mapped to the server. You can do the same thing with ATTACH.EXE:
ATTACH TARGET_SERVER/loginidtotry <enter>
The same thing will happen as the MAP command. If valid, you will be prompted for a password. If not, you get an error.
Another program to check for valid users and the presence of a password is CHKNULL.EXE by itsme. This program checks for users and whether they have a password assigned.
Before I start this section, let me recommend another solution, my God, ANY other solution is better than this! If you are running 3.x, jump to the end of this section.
The secret method is the method of using a DOS-based sector editor to edit the entry in the FAT, and reset the bindery to default upon server reboot. This gives you Supervisor and Guest with no passwords. The method was taught in case you lost Supervisor on a Netware 2.15 server and you had no supe equivalent accounts created. It also saves the server from a wipe and reboot in case the Supervisor account is corrupt, deleted, or trashed.
While you get a variety of answers from Novell about this technique, from it doesn't work to it is technically impossible, truth be it it can be done. Here are the steps, as quoted from comp.os.netware.security, with my comments in [brackets]:
[start of quote]
A Netware Server is supposed to be a very safe place to keep your files. Only people with the right password will have access to the data stored there. The Supervisor (or Admin) user's password is usually the most well kept secret in the company, since anyone that has that code could simply log to the server and do anything he/she wants. But what happens if this password is lost and there's no user that is security-equivalent to the supervisor? [Use SETPWD.NLM, instead of this process, see 01-10 below - S.N.] What happens if the password system is somehow damaged and no one can log to the network? According to the manual, there's simply no way out. You would have to reinstall the server and try to find your most recent backup.
Fortunately, there is a very interesting way to gain complete access to a Netware server without knowing the Supervisor's (or Admin's) password. You may imagine that you would have to learn complex decryption techniques or even type in a long C program, but that's not the case. The trick is so simple and generic that it will work the same way for Netware 2.x, 3.x and 4.x.
The idea is to fool Netware to think that you have just installed the server and that no security system has been estabilished yet. Just after a Netware 2.x or 3.x server is installed, the Supervisor's password is null and you can log in with no restriction. Netware 4.x works slightly differently, but it also allows anyone to log in after the initial installation, since the installer is asked to enter a password for the Admin user.
But how can you make the server think it has just been installed without actually reinstalling the server and losing all data on the disk? Simple. You just delete the files that contain the security system. In Netware 2.x, all security information is stored in two files (NET$BIND.SYS and NET$BVAL.SYS). Netware 3.x stores that information in three files (NET$OBJ.SYS, NET$VAL.SYS and NET$PROP.SYS). The all new Netware 4.x system stores all login names and passwords in five different files (PARTITIO.NDS, BLOCK.NDS, ENTRY.NDS, VALUE.NDS and UNINSTAL.NDS [This last file may not be there, don't worry - S.N.]).
One last question remains. How can we delete these files if we don't have access to the network, anyway? The answer is, again, simple. Altough the people from Novell did a very good job encrypting passwords, they let all directory information easy to find and change if you can access the server's disk directly, using common utilities like Norton's Disk Edit. Using this utility as an example, I'll give a step-by-step procedure to make these files vanish. All you need is a bootable DOS disk, Norton Utilities' Emergency Disk containing the DiskEdit program and some time near the server.
Boot the server and go to the DOS prompt. To do this, just let the network boot normally and then use the DOWN and EXIT commands. This procedure does not work on old Netware 2.x servers and in some installations where DOS has been removed from memory. In those cases, you'll have to use a DOS bootable disk.
Run Norton's DiskEdit utility from drive A:
Select "Tools" in the main menu and then select "Configuration". At the configuration window, uncheck the "Read-Only" checkbox. And be very careful with everything you type after this point.
Select "Object" and then "Drive". At the window, select the C: drive and make sure you check the button "physical drive". After that, you'll be looking at your physical disk and you be able to see (and change) everything on it.
Select "Tools" and then "Find". Here, you'll enter the name of the file you are trying to find. Use "NET$BIND" for Netware 2, "NET$PROP.SYS" for Netware 3 and "PARTITIO.NDS" for Netware 4. It is possible that you find these strings in a place that is not the Netware directory. If the file names are not all near each other and proportionaly separated by some unreadable codes (at least 32 bytes between them), then you it's not the place we are looking for. In that case, you'll have to keep searching by selecting "Tools" and then "Find again". [In Netware 3.x, you can change all occurences of the bindery files and it should still work okay, I've done it before. - S.N.]
You found the directory and you are ready to change it. Instead of deleting the files, you'll be renaming them. This will avoid problems with the directory structure (like lost FAT chains). Just type "OLD" over the existing "SYS" or "NDS" extension. Be extremely careful and don't change anything else.
Select "Tools" and then "Find again". Since Netware store the directory information in two different places, you have to find the other copy and change it the same way. This will again prevent directory structure problems.
Exit Norton Disk Edit and boot the server again. If you're running Netware 2 or 3, your server would be already accessible. Just go to any station and log in as user Supervisor. No password will be asked. If you're running Netware 4, there is one last step.
Load Netware 4 install utility (just type LOAD INSTALL at the console prompt) and select the options to install the Directory Services. You be prompted for the Admin password while doing this. After that, you may go to any station and log in as user Admin, using the password that you have selected.
What I did with Norton's Disk Edit could be done with any disk editing utility with a "Search" feature. This trick has helped me save many network supervisors in the last years. I would just like to remind you that no one should break into a netware server unless authorized to do it by the company that owns the server. But you problably know that already.
[end of quote]
I actually had this typed up but kept changing it, so I stole this quote from the newsgroup to save me retyping ;-)
Now the quicky for 3.x users. Use LASTHOPE.NLM, which renames the bindery and downs the server. Reboot and you have Supe and Guest, no password.
The cheesy way is the way that will get you in, but it will be obvious to the server's admin that the server has been compromised. This technique works for 3.11.
Using NW-HACK.EXE, if the Supervisor is logged in NW-HACK does the following things:
What the admin will do is remove the supe rights from all accounts that are not supposed to have it and change the Supervisor password back. The only thing you can do is leave a backdoor for yourself (see next question).
Once you are in, you want to leave a way back with supe equivalency. You can use SUPER.EXE, written for the express purpose of allowing the non-supe user to toggle on and off supe equivalency. If you use the cheesy way in (previous question), you turn on the toggle before the admin removes your supe equivalency. If you gain access to a supe equivalent account, give Guest supe equivalency and then login as Guest and toggle it on. Now get back in as the original supe account and remove the supe equivalency. Now Guest can toggle on supe equivalency whenever it's convenient.
Of course Guest doesn't have to be used, it could be another account, like an account used for e-mail administration or an e-mail router, a gateway's account, you get the idea.
Now SUPER.EXE is not completely clean. Running the Security utility or Bindfix will give away that an account has been altered at the bindery level, but the only way for an admin to clear the error is to delete and rebuild the account.
Another backdoor is outlined in section 01-2 regarding the replacement LOGIN.EXE and PROP.EXE
Yes. If a user is logging in and the password is being transmitted to the server unencrypted, it will show up as plain text in the trace. If the site uses telnet and ftp, capturing those password will come in handy. Outside of gaining access to another system, many users will make their passwords the same across all systems.
For a list of DOS-based sniffers, see the alt.2600/#hack FAQ. I personally prefer the Network General Sniffer ;-)
You can use a brute force cracker on captured encrypted passwords. As I have more tools and details, I will provide them here.
Packet signatures works by using an intermediate step during the encrypted password login call, to calculate a 64-bit signature. This block is never transmitted over the wire, but it is used as the basis for a cryptographically strong signature ("secure hash") on the most important part of each NCP packet exchange. A signed packet can indeed be taken as proof sufficient that the packet came from the claimed PC.
NCP Packet Signature is Novell's answer to the work of the folks in the Netherlands in hacking Netware. The idea behind it is to prevent forged packets and unauthorized Supervisor access. It is an add-on option in 3.11, but a part of the system with 3.12 and 4.x. Here are the signature levels at the client and server:
Packet Signature Option and meaning:
0 = Don't do packet signatures
1 = Do packet signatures if required
2 = Do packet signatures if you can but don't if the other end doesn't support them
3 = Require packet signatures
You can set the same settings at the workstation server. The default for packet signatures is 2 at the server and client. If you wish to use a tool like HACK.EXE, try setting the signature level at 0 on the client by adding Signature Level=0 in the client's NET.CFG. If packet signatures are required at the server you won't even get logged in, but if you get logged in, hack away.
If you wish to change the signature level at the server, use a set command at the server console:
SET NCP PACKET SIGNATURE OPTION=2
You can load SETPWD at the console or via RCONSOLE. If you use RCONSOLE, use the Transfer Files To Server option and put the file in SYS:SYSTEM.
For 3.x:
LOAD [path if not in SYS:SYSTEM]SETPWD [username] [newpassword]
For 4.x:
set bindery context = [context, e.g. hack.corp.us]
LOAD [path if not in SYS:SYSTEM]SETPWD [username] [newpassword]
In 4.x the change is replicated so you have access to all the other servers in the tree. And don't forget, you must follow the password requirements in SYSCON for this to work. That is, if the account you are changing normally requires a 6 character password, then you'll need to supply a 6 character password.
You must be at the console to do this:
<left-shift><right-shift><alt><esc> (Enters debugger)
type c VerifyPassword=B8 0 0 0 0 C3
type g
This disables the password checking. Now Supe won't ask for a password. To restore password checking from debugger, do this:
first type d VerifyPassword 5 and write down the 5 byte response,
then type c VerifyPassword=xx xx xx xx xx
then type g