Crypto

Fun with SolarWinds Orion Cryptography

Introduction

We run into a wide variety of network management solutions during our security assessments and penetration tests. The SolarWinds Orion product suite in particular is popular with network administrators and IT teams of all sizes. The Orion platform includes modules such as the Network Engineers Toolkit, Web Performance Monitor, and Network Configuration Management, among many others. We found some fun ways to abuse this product during security tests and wanted to share our notes with the community.

The Orion product uses a Microsoft SQL Server backend to store information about user accounts, network devices, and the credentials used to manage these devices. An Orion system used to manage a large network will typically use a standalone SQL Server installation, while smaller networks will use a local SQL Server Express instance. Since the Orion server houses credentials and can often be used to push and pull network device configurations, it can be a gold mine for expanding access during a penetration test.

Gaining access to the web console without a login

The Orion product is typically managed from the web console; this can use a local account database or an existing Active Directory service. An attacker can then monitor network traffic between the Orion server and a separate SQL Server instance, extracting hashed user passwords and encrypted network device credentials. An attacker that can man-in-the-middle the SQL Server communication can use this to login to the Orion web console with an arbitrary password by replacing the password hash when the web server queries the Accounts table during login. If direct access to the SQL Server database for Orion is possible, a modification to the Accounts table will allow for easy access to the console. If the attacker has local administrator access to the Orion server, they can modify the Accounts table using the Orion Database Manager GUI application. Regardless of how an attacker gains access to the Accounts table, the easiest approach to gaining access is to backup the existing hash, then replace the PasswordHash column for an enabled administrative user.  An empty PasswordHash for the "admin" user account corresponds to the following string:"

/+PA4Zck3arkLA7iwWIugnAEoq4ocRsYjF7lzgQWvJc+pepPz2a5z/L1Pz3c366Y/CasJIa7enKFDPJCWNiKRg==

Note that this password hash is only valid for the "admin" user (see notes below on salting). The screenshot below shows the SQL query to reset the "admin" account to the empty password, using the SolarWinds Database Manager GUI (via local administrator access over Remote Desktop).

Replace_PasswordHash.png

Once the PasswordHash has been replaced (or temporarily intercepted), the attacker can login with an empty password for the associated user account.  

 

SolarWinds Orion "Accounts" table password hashing

Orion password hashing is a variant of a salted SHA512 hash. The hash is computed by first generating a salt that consists of the lowercase username. If the salt is less than 8 bytes long, it is appended with bytes from the string "1244352345234" until it is 8 bytes. For example, the salt for username "ADMIN" would become "admin124", while the salt for "Bo" would become "bo124435". Once the salt has been calculated, a RFC2898 PBKFD2 is generated using the default iteration count of 1000 and the SHA1 hash algorithm. Finally, a SHA512 hash of the PBKDF2 output is taken and encoded using Base64. It doesn't appear that any existing tools support cracking passwords in this format, but Hashcat comes close with PBKDF2-HMAC-SHA1(sha1:1000) support, and is only missing the final call to SHA512(). This hashing function has been implemented in the Ruby script hash-password.rb.

 

Harvesting stored network credentials from the database

SolarWinds Orion stores network credentials within the SQL Server database tables. Some of these credentials, such as SNMP v1/v2c community strings, are stored in clear-text, while most are encrypted using a RSA key located in the Orion server local certificate store. Network credentials can be harvested from the database through passive monitoring or active exports, in the latter case, either using standard SQL Server management tools, or if local administrator access has been obtained on the Orion server, using the Database Manager GUI application. A partial list of tables that should be exported to collect credentials includes:

  • Accounts (Username, PasswordHash)

  • Credential (ID, Name)

  • CredentialProperty (ID, Name, Value)

  • Nodes (IPAddress, Community, RWCommunity)

  • NCM_Nodes [View] (Name, Username, Password , EnableLevel , EnablePassword)

  • NCM_GlobalSettings (SettingName, SettingValue)

  • NCM_NodeProperties (Username, Password, EnableLevel, EnablePassword)

  • NCM_ConfigSnippets (AdvancedScript)

  • NCM_ConnectionProfiles (Name, Username, Password, EnableLevel, EnablePassword)

  • SSH_Sessions (HostName, Username, Password)

  • SSO_Tokens

  • Traps (Community)

  • Traps (CommunityStrings (Community)

Decrypting stored network credentials

Network credentials stored within the SQL Server database are encrypted with a RSA key located in the local machine certificate store of the Orion server. For most SQL tables, these credentials are prefixed with the string "SWEN__", while the SSH sessions table uses a raw form without the prefix. To decrypt these credentials, the RSA key for the SolarWinds-Orion certificate must be exported from the system. This typically requires local administrator access and an elevated command shell on the Orion server. To export the key, use certutil:

C:\Temp> certutil -exportPFX -p Atredis my SolarWinds-Orion orion.pfx
my "Personal"
================ Certificate 0 ================
Serial Number: c0e0b5d49a84818048d614012d6c7497
Issuer: CN=SolarWinds-Orion
 NotBefore: 10/21/2018 6:26 PM
 NotAfter: 12/31/2039 6:59 PM
Subject: CN=SolarWinds-Orion
Signature matches Public Key
Root Certificate: Subject matches Issuer
Cert Hash(sha1): e60003315dd42f55adeb7f4c2071b6e9bc9dd996
  Key Container = 9292e92a-9fb9-4881-94cd-c8c582550268
  Unique container name: 7f96c35203d32d4fae1724bb52f38232_c5c554db-595b-4464-ac33-102a5379ad51
  Provider = Microsoft Strong Cryptographic Provider
Encryption test passed
CertUtil: -exportPFX command completed successfully.

If an error is returned stating “Keyset does not exist”, this typically means that the command was not run as an administrative user with elevated privileges. If certutils does not work for some reason, or if the cert has been marked unexportable, you can still export the private key using Jailbreak or Mimikatz.

Next, the PFX needs to be converted to a standard OpenSSL PEM file. The openssl command handles this with the following syntax: 

C:\Temp> openssl pkcs12 -in orion.pfx -out orion.pem -nodes -password pass:Atredis

Using the clear-text orion.pem file, the credentials in the exported database tables can be decrypted using the ruby scripts; decrypt-swen-credentials.rb and decrypt-ssh-sessions.rb. These scripts will read the RSA key from “orion.pem” and decrypt credentials found in all files passed as arguments, saving the results to files with the “.dec” extension. the Database Manager GUI includes a handy “Export to CSV” button that simplifies this process. The decrypt-ssh-sessions.rb script looks for the password fields in the SSHSessions table, which does not use the “SWEN” prefix. The following example demonstrates using the decrypt-swen-credentials.rb script against an export of the NCM_GlobalSettings table.

$ ruby decrypt-swen-credentials.rb NCM_GlobalSettings.csv 
$ cat NCM_GlobalSettings.csv.dec
"SettingName","SettingValue"
"GlobalConfigRequestProtocol","SNMP"
"GlobalConfigTransferProtocol","TFTP"
"GlobalEnableLevel","enable"
"GlobalEnablePassword","ubersecret!"
"GlobalExecProtocol","SSH auto"
"GlobalPassword","secret!"
"GlobalSSHPort","22"
"GlobalTelnetPort","23"
"GlobalUsername","solarwinds"

Conclusion

The SolarWinds Orion platform is a lot of fun for penetration testers, as it can act as a credential store, configuration management system, and remote command execution platform, depending on what modules are configured. As an added bonus, highly segmented networks often whitelist their network monitoring servers, making the SolarWinds server an attractive target for lateral movement. Although the password hashing and credential encryption is relatively sane from a security standpoint, they can be abused with the right tools. I hope the information above is useful and convinces you to pay special attention to network monitoring applications on your next penetration test.

-HD