hacktricks/macos-hardening/macos-red-teaming/macos-keychain.md
Carlos Polop da6aaca1c2 a
2024-02-08 22:36:15 +01:00

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# macOS Keychain
<details>
<summary><strong>Learn AWS hacking from zero to hero with</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE (HackTricks AWS Red Team Expert)</strong></a><strong>!</strong></summary>
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</details>
## Main Keychains
* The **User Keychain** (`~/Library/Keychains/login.keycahin-db`), which is used to store **user-specific credentials** like application passwords, internet passwords, user-generated certificates, network passwords, and user-generated public/private keys.
* The **System Keychain** (`/Library/Keychains/System.keychain`), which stores **system-wide credentials** such as WiFi passwords, system root certificates, system private keys, and system application passwords.
### Password Keychain Access
These files, while they do not have inherent protection and can be **downloaded**, are encrypted and require the **user's plaintext password to be decrypted**. A tool like [**Chainbreaker**](https://github.com/n0fate/chainbreaker) could be used for decryption.
## Keychain Entries Protections
### ACLs
Each entry in the keychain is governed by **Access Control Lists (ACLs)** which dictate who can perform various actions on the keychain entry, including:
* **ACLAuhtorizationExportClear**: Allows the holder to get the clear text of the secret.
* **ACLAuhtorizationExportWrapped**: Allows the holder to get the clear text encrypted with another provided password.
* **ACLAuhtorizationAny**: Allows the holder to perform any action.
The ACLs are further accompanied by a **list of trusted applications** that can perform these actions without prompting. This could be:
* &#x20;**N`il`** (no authorization required, **everyone is trusted**)
* An **empty** list (**nobody** is trusted)
* **List** of specific **applications**.
Also the entry might contain the key **`ACLAuthorizationPartitionID`,** which is use to identify the **teamid, apple,** and **cdhash.**
* If the **teamid** is specified, then in order to **access the entry** value **withuot** a **prompt** the used application must have the **same teamid**.
* If the **apple** is specified, then the app needs to be **signed** by **Apple**.
* If the **cdhash** is indicated, then **app** must have the specific **cdhash**.
### Creating a Keychain Entry
When a **new** **entry** is created using **`Keychain Access.app`**, the following rules apply:
* All apps can encrypt.
* **No apps** can export/decrypt (without prompting the user).
* All apps can see the integrity check.
* No apps can change ACLs.
* The **partitionID** is set to **`apple`**.
When an **application creates an entry in the keychain**, the rules are slightly different:
* All apps can encrypt.
* Only the **creating application** (or any other apps explicitly added) can export/decrypt (without prompting the user).
* All apps can see the integrity check.
* No apps can change the ACLs.
* The **partitionID** is set to **`teamid:[teamID here]`**.
## Accessing the Keychain
### `security`
```bash
# Dump all metadata and decrypted secrets (a lot of pop-ups)
security dump-keychain -a -d
# Find generic password for the "Slack" account and print the secrets
security find-generic-password -a "Slack" -g
# Change the specified entrys PartitionID entry
security set-generic-password-parition-list -s "test service" -a "test acount" -S
```
### APIs
{% hint style="success" %}
The **keychain enumeration and dumping** of secrets that **won't generate a prompt** can be done with the tool [**LockSmith**](https://github.com/its-a-feature/LockSmith)
{% endhint %}
List and get **info** about each keychain entry:
* The API **`SecItemCopyMatching`** gives info about each entry and there are some attributes you can set when using it:
* **`kSecReturnData`**: If true, it will try to decrypt the data (set to false to avoid potential pop-ups)
* **`kSecReturnRef`**: Get also reference to keychain item (set to true in case later you see you can decrypt without pop-up)
* **`kSecReturnAttributes`**: Get metadata about entries
* **`kSecMatchLimit`**: How many results to return
* **`kSecClass`**: What kind of keychain entry
Get **ACLs** of each entry:
* With the API **`SecAccessCopyACLList`** you can get the **ACL for the keychain item**, and it will return a list of ACLs (like `ACLAuhtorizationExportClear` and the others previously mentioned) where each list has:
* Description
* **Trusted Application List**. This could be:
* An app: /Applications/Slack.app
* A binary: /usr/libexec/airportd
* A group: group://AirPort
Export the data:
* The API **`SecKeychainItemCopyContent`** gets the plaintext
* The API **`SecItemExport`** exports the keys and certificates but might have to set passwords to export the content encrypted
And these are the **requirements** to be able to **export a secret without a prompt**:
* If **1+ trusted** apps listed:
* Need the appropriate **authorizations** (**`Nil`**, or be **part** of the allowed list of apps in the authorization to access the secret info)
* Need code signature to match **PartitionID**
* Need code signature to match that of one **trusted app** (or be a member of the right KeychainAccessGroup)
* If **all applications trusted**:
* Need the appropriate **authorizations**
* Need code signature to match **PartitionID**
* If **no PartitionID**, then this isn't needed
{% hint style="danger" %}
Therefore, if there is **1 application listed**, you need to **inject code in that application**.
If **apple** is indicated in the **partitionID**, you could access it with **`osascript`** so anything that is trusting all applications with apple in the partitionID. **`Python`** could also be used for this.
{% endhint %}
### Two additional attributes
* **Invisible**: It's a boolean flag to **hide** the entry from the **UI** Keychain app
* **General**: It's to store **metadata** (so it's NOT ENCRYPTED)
* Microsoft was storing in plain text all the refresh tokens to access sensitive endpoint.
## References
* [**#OBTS v5.0: "Lock Picking the macOS Keychain" - Cody Thomas**](https://www.youtube.com/watch?v=jKE1ZW33JpY)
<details>
<summary><strong>Learn AWS hacking from zero to hero with</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE (HackTricks AWS Red Team Expert)</strong></a><strong>!</strong></summary>
Other ways to support HackTricks:
* If you want to see your **company advertised in HackTricks** or **download HackTricks in PDF** Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@carlospolopm**](https://twitter.com/hacktricks_live)**.**
* **Share your hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.
</details>