rpcclient – 135 – TCP/UDP

Network Attack

What is a RID

A Relative Identifier (RID) is a unique identifier (represented in hexadecimal format) utilized by Windows to track and identify objects. To explain how this fits in, let’s look at the examples below:

  • The SID for the NAME_DOMAIN.LOCAL domain is: S-1-5-21-1038751438-1834703946-36937684957.
  • When an object is created within a domain, the number above (SID) will be combined with a RID to make a unique value used to represent the object.
  • So the domain user john with a RID:[0x457] Hex 0x457 would = decimal 1111, will have a full user SID of: S-1-5-21-1038751438-1834703946-36937684957-1111.
  • This is unique to the john object in the NAME_DOMAIN.LOCAL domain and you will never see this paired value tied to another object in this domain or any other.

Definition from here.

Enumeration with rpcclient

Pat of this section was extracted from book “Network Security Assesment 3rd EditionYou can use the Samba rpcclient utility to interact with RPC endpoints via named pipes. The following lists commands that you can issue to SAMR, LSARPC, and LSARPC-DS interfaces upon establishing a SMB session (often requiring credentials).

Server Info

  • Server Info: srvinfo

Users enumeration

  • List users: querydispinfo and enumdomusers
  • Get user details: queryuser <0xrid>
  • Get user groups: queryusergroups <0xrid>
  • GET SID of a user: lookupnames <username>
  • Get users aliases: queryuseraliases [builtin|domain] <sid>
# Brute-Force users RIDs
for i in $(seq 500 1100); do
    rpcclient -N -U "" 10.129.14.128 -c "queryuser 0x$(printf '%x\n' $i)" | grep "User Name\|user_rid\|group_rid" && echo "";
done

# You can also use samrdump.py for this purpose

Groups enumeration

  • List groups: enumdomgroups
  • Get group details: querygroup <0xrid>
  • Get group members: querygroupmem <0xrid>

Aliasgroups enumeration

  • List alias: enumalsgroups <builtin|domain>
  • Get members: queryaliasmem builtin|domain <0xrid>

Domains enumeration

  • List domains: enumdomains
  • Get SID: lsaquery
  • Domain info: querydominfo

Shares enumeration

  • Enumerate all available shares: netshareenumall
  • Info about a share: netsharegetinfo <share>

More SIDs

  • Find SIDs by name: lookupnames <username>
  • Find more SIDs: lsaenumsid
  • RID cycling (check more SIDs): lookupsids <sid>

Extra commands

CommandInterfaceDescription
queryuserSAMRRetrieve user information
querygroup Retrieve group information
querydominfo Retrieve domain information
enumdomusers Enumerate domain users
enumdomgroups Enumerate domain groups
createdomuser Create a domain user
deletedomuser Delete a domain user
lookupnamesLSARPCLook up usernames to SID values
lookupsids Look up SIDs to usernames (RID cycling)
lsaaddacctrights Add rights to a user account
lsaremoveacctrights Remove rights from a user account
dsroledominfoLSARPC-DSGet primary domain information
dsenumdomtrusts Enumerate trusted domains within an AD forest

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