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Keychain

Keychains are the built-in way for macOS to keep track of users' passwords and credentials for many services and features such as WiFi passwords, websites, secure notes, certificates, and Kerberos. Keychain files are located in ~/Library/Keychains/,/Library/Keychains/, and /Network/Library/Keychains/. [1] The security command-line utility, which is built into macOS by default, provides a useful way to manage these credentials.

To manage their credentials, users have to use additional credentials to access their keychain. If an adversary knows the credentials for the login keychain, then they can get access to all the other credentials stored in this vault. [2] By default, the passphrase for the keychain is the user’s logon credentials.

ID: T1142

Tactic: Credential Access

Platform:  macOS

Permissions Required:  Administrator

Data Sources:  System calls, Process monitoring

Version: 1.0

Examples

NameDescription
Calisto

Calisto collects Keychain storage data and copies those passwords/tokens to a file.[3][4]

iKitten

iKitten collects the keychains on the system.[5]

Mitigation

The password for the user's login keychain can be changed from the user's login password. This increases the complexity for an adversary because they need to know an additional password.

Detection

Unlocking the keychain and using passwords from it is a very common process, so there is likely to be a lot of noise in any detection technique. Monitoring of system calls to the keychain can help determine if there is a suspicious process trying to access it.

References