Query: detection engineering for Credentials from Web Browsers
Matching passage: T1555.003 Credentials from Web Browsers. Tactics: credential access. Description: Adversaries may acquire credentials from web browsers by reading files specific to the target browser.(Citation: Talos Olympic Destroyer 2018) Web browsers commonly save credentials such as website usernames and passwords so that they do not need to be entered manually in the future. Web browsers typically store the credentials in an encrypted format within a credential store; however, methods exist to extract plaintext credentials from web browsers. For example, on Windows systems, encrypted credentials may be obtained from Google Chrome by reading a database file, <code>AppData\Local\Google\Chrome\User Data\Default\Login Data</code> and executing a SQL query: <code>SELECT action_url, username_value, password_value FROM logins;</code>. The plaintext password can then be obtained by passing the encrypted credentials to the Windows API function <code>CryptUnprotectData</code>, which uses the victim’s cached logon credentials as the decryption key.(Citation: Microsoft CryptUnprotectData April 2018) Adversaries have executed similar procedures for common web browsers such as FireFox, Safari, Edge, etc.(Citation: Proofpoint Vega Credential Stealer May 2018)(Citation: FireEye HawkEye Malware July 2017) Windows stores Internet Explorer and Microsoft Edge credentials in Credential Lockers managed by the [Windows Credential Manager](https://attack.mitre.org/techniques/T1555/004). Adversaries may also acquire credentials by searching web browser process memory for patterns that commonly match credentials.(Citation: GitHub Mimikittenz July 2016) After acquiring credentials from web browsers, adversaries may attempt to recycle the credentials across different systems and/or accounts in order to expand access. This can result in significantly furthering an adversary's objective in cases where credentials gained from web browsers overlap with privileged accounts (e.g. domain administrator).
Near-miss passage: T1555.004 Windows Credential Manager. Tactics: credential access. Description: Adversaries may acquire credentials from the Windows Credential Manager. The Credential Manager stores credentials for signing into websites, applications, and/or devices that request authentication through NTLM or Kerberos in Credential Lockers (previously known as Windows Vaults).(Citation: Microsoft Credential Manager store)(Citation: Microsoft Credential Locker) The Windows Credential Manager separates website credentials from application or network credentials in two lockers. As part of [Credentials from Web Browsers](https://attack.mitre.org/techniques/T1555/003), Internet Explorer and Microsoft Edge website credentials are managed by the Credential Manager and are stored in the Web Credentials locker. Application and network credentials are stored in the Windows Credentials locker. Credential Lockers store credentials in encrypted `.vcrd` files, located under `%Systemdrive%\Users\\[Username]\AppData\Local\Microsoft\\[Vault/Credentials]\`. The encryption key can be found in a file named <code>Policy.vpol</code>, typically located in the same folder as the credentials.(Citation: passcape Windows Vault)(Citation: Malwarebytes The Windows Vault) Adversaries may list credentials managed by the Windows Credential Manager through several mechanisms. <code>vaultcmd.exe</code> is a native Windows executable that can be used to enumerate credentials stored in the Credential Locker through a command-line interface. Adversaries may also gather credentials by directly reading files located inside of the Credential Lockers. Windows APIs, such as <code>CredEnumerateA</code>, may also be absued to list credentials managed by the Credential Manager.(Citation: Microsoft CredEnumerate)(Citation: Delpy Mimikatz Crendential Manager) Adversaries may also obtain credentials from credential backups. Credential backups and restorations may be performed by running <code>rundll32.exe keymgr.dll KRShowKeyMgr</code> then selecting the “Back up...” button on the “Stored User Names and Pas