Adversaries may communicate using OSI application layer protocols to avoid detection/network filtering by blending in with existing traffic. Commands to the remote system, and often the results of those commands, will be embedded within the protocol traffic between the client and server.Adversaries may utilize many different protocols, including those used for web browsing, transferring files, electronic mail, or DNS. For connections that occur internally within an enclave (such as those between a proxy or pivot node and other nodes), commonly used protocols are SMB, SSH, or RDP.
Once established within a system or network, an adversary may use automated techniques for collecting internal data. Methods for performing this technique could include use of a [Command and Scripting Interpreter](https://app.tidalcyber.com/technique/a2184d53-63b1-4c40-81ed-da799080c36c) to search for and copy information fitting set criteria such as file type, location, or name at specific time intervals. In cloud-based environments, adversaries may also use cloud APIs, command line interfaces, or extract, transform, and load (ETL) services to automatically collect data. This functionality could also be built into remote access tools.This technique may incorporate use of other techniques such as [File and Directory Discovery](https://app.tidalcyber.com/technique/1492c4ba-c933-47b8-953d-6de3db8cfce8) and [Lateral Tool Transfer](https://app.tidalcyber.com/technique/3dea57fc-3131-408b-a1fd-ff2eea1d858f) to identify and move files, as well as [Cloud Service Dashboard](https://app.tidalcyber.com/technique/315ce434-ad6d-4dae-a1dd-6db944a44422) and [Cloud Storage Object Discovery](https://app.tidalcyber.com/technique/92761d92-a288-4407-a112-bb2720f07d07) to identify resources in cloud environments.
Adversaries may exfiltrate data, such as sensitive documents, through the use of automated processing after being gathered during Collection.When automated exfiltration is used, other exfiltration techniques likely apply as well to transfer the information out of the network, such as [Exfiltration Over C2 Channel](https://app.tidalcyber.com/technique/89203cae-d3f1-4eef-9b5a-29042eb05d19) and [Exfiltration Over Alternative Protocol](https://app.tidalcyber.com/technique/192d25ea-bae1-48e4-88de-e0acd481ab88).
Adversaries may acquire credentials from web browsers by reading files specific to the target browser.[[Talos Olympic Destroyer 2018](https://app.tidalcyber.com/references/25a2e179-7abd-4091-8af4-e9d2bf24ef11)] 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, AppData\Local\Google\Chrome\User Data\Default\Login Data and executing a SQL query: SELECT action_url, username_value, password_value FROM logins;. The plaintext password can then be obtained by passing the encrypted credentials to the Windows API function CryptUnprotectData, which uses the victim’s cached logon credentials as the decryption key.[[Microsoft CryptUnprotectData April 2018](https://app.tidalcyber.com/references/258088ae-96c2-4520-8eb5-1a7e540a9a24)]Adversaries have executed similar procedures for common web browsers such as FireFox, Safari, Edge, etc.[[Proofpoint Vega Credential Stealer May 2018](https://app.tidalcyber.com/references/c52fe62f-4df4-43b0-a126-2df07dc61fc0)][[FireEye HawkEye Malware July 2017](https://app.tidalcyber.com/references/7ad228a8-5450-45ec-86fc-ea038f7c6ef7)] Windows stores Internet Explorer and Microsoft Edge credentials in Credential Lockers managed by the [Windows Credential Manager](https://app.tidalcyber.com/technique/9503955c-fa53-452a-b717-7e23bfb4df83).
Adversaries may also acquire credentials by searching web browser process memory for patterns that commonly match credentials.[[GitHub Mimikittenz July 2016](https://app.tidalcyber.com/references/2e0a95b2-3f9a-4638-9bc5-ff1f3ac2af4b)]
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).
Adversaries may search local system sources, such as file systems and configuration files or local databases, to find files of interest and sensitive data prior to Exfiltration.Adversaries may do this using a [Command and Scripting Interpreter](https://app.tidalcyber.com/technique/a2184d53-63b1-4c40-81ed-da799080c36c), such as [cmd](https://app.tidalcyber.com/software/98d89476-63ec-4baf-b2b3-86c52170f5d8) as well as a [Network Device CLI](https://app.tidalcyber.com/technique/284bfbb3-99f0-4c3d-bc1f-ab74065b7907), which have functionality to interact with the file system to gather information.[[show_run_config_cmd_cisco](https://app.tidalcyber.com/references/5a68a45a-a53e-5d73-a82a-0cc951071aef)] Adversaries may also use [Automated Collection](https://app.tidalcyber.com/technique/107ad6c5-79b1-468c-9519-1578bee2ac49) on the local system.
Adversaries may use [Obfuscated Files or Information](https://app.tidalcyber.com/technique/046cc07e-8700-4536-9c5b-6ecb384f52b0) to hide artifacts of an intrusion from analysis. They may require separate mechanisms to decode or deobfuscate that information depending on how they intend to use it. Methods for doing that include built-in functionality of malware or by using utilities present on the system.One such example is the use of [certutil](https://app.tidalcyber.com/software/2fe21578-ee31-4ee8-b6ab-b5f76f97d043) to decode a remote access tool portable executable file that has been hidden inside a certificate file.[[Malwarebytes Targeted Attack against Saudi Arabia](https://app.tidalcyber.com/references/735647f9-9cd4-4a20-8812-4671a3358e46)] Another example is using the Windows copy /b command to reassemble binary fragments into a malicious payload.[[Carbon Black Obfuscation Sept 2016](https://app.tidalcyber.com/references/bed8ae68-9738-46fb-abc9-0004fa35636a)]Sometimes a user’s action may be required to open it for deobfuscation or decryption as part of [User Execution](https://app.tidalcyber.com/technique/b84435ab-2ff4-4b6f-ba71-b4b815474872). The user may also be required to input a password to open a password protected compressed/encrypted file that was provided by the adversary. [[Volexity PowerDuke November 2016](https://app.tidalcyber.com/references/4026c055-6020-41bb-a4c8-54b308867023)]
Adversaries may enumerate files and directories or may search in specific locations of a host or network share for certain information within a file system. Adversaries may use the information from [File and Directory Discovery](https://app.tidalcyber.com/technique/1492c4ba-c933-47b8-953d-6de3db8cfce8) during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions.Many command shell utilities can be used to obtain this information. Examples include dir, tree, ls, find, and locate.[[Windows Commands JPCERT](https://app.tidalcyber.com/references/9d935f7f-bc2a-4d09-a51a-82074ffd7d77)] Custom tools may also be used to gather file and directory information and interact with the [Native API](https://app.tidalcyber.com/technique/1120f5ec-ef1b-4596-8d8b-a3979a766560). Adversaries may also leverage a [Network Device CLI](https://app.tidalcyber.com/technique/284bfbb3-99f0-4c3d-bc1f-ab74065b7907) on network devices to gather file and directory information (e.g. dir, show flash, and/or nvram).[[US-CERT-TA18-106A](https://app.tidalcyber.com/references/1fe55557-94af-4697-a675-884701f70f2a)]
Adversaries may maliciously modify components of a victim environment in order to hinder or disable defensive mechanisms. This not only involves impairing preventative defenses, such as firewalls and anti-virus, but also detection capabilities that defenders can use to audit activity and identify malicious behavior. This may also span both native defenses as well as supplemental capabilities installed by users and administrators.Adversaries may also impair routine operations that contribute to defensive hygiene, such as blocking users from logging out of a computer or stopping it from being shut down. These restrictions can further enable malicious operations as well as the continued propagation of incidents.[[Emotet shutdown](https://app.tidalcyber.com/references/02e6c7bf-f81c-53a3-b771-fd77d4cdb5a0)]Adversaries could also target event aggregation and analysis mechanisms, or otherwise disrupt these procedures by altering other system components.
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials. Web applications and services often use session cookies as an authentication token after a user has authenticated to a website.Cookies are often valid for an extended period of time, even if the web application is not actively used. Cookies can be found on disk, in the process memory of the browser, and in network traffic to remote systems. Additionally, other applications on the targets machine might store sensitive authentication cookies in memory (e.g. apps which authenticate to cloud services). Session cookies can be used to bypasses some multi-factor authentication protocols.[[Pass The Cookie](https://app.tidalcyber.com/references/dc67930f-5c7b-41be-97e9-d8f4a55e6019)]There are several examples of malware targeting cookies from web browsers on the local system.[[Kaspersky TajMahal April 2019](https://app.tidalcyber.com/references/1ed20522-52ae-4d0c-b42e-c680490958ac)][[Unit 42 Mac Crypto Cookies January 2019](https://app.tidalcyber.com/references/0a88e730-8ed2-4983-8f11-2cb2e4abfe3e)] There are also open source frameworks such as Evilginx 2 and Muraena that can gather session cookies through a malicious proxy (ex: [Adversary-in-the-Middle](https://app.tidalcyber.com/technique/d98dbf30-c454-42ff-a9f3-2cd3319cc0d9)) that can be set up by an adversary and used in phishing campaigns.[[Github evilginx2](https://app.tidalcyber.com/references/322e5d90-5095-47ea-b0e2-e7e5fb45fcca)][[GitHub Mauraena](https://app.tidalcyber.com/references/578ecf62-b546-4f52-9d50-92557edf2dd4)]
After an adversary acquires a valid cookie, they can then perform a [Web Session Cookie](https://app.tidalcyber.com/technique/d36a5323-e249-44e8-9c8b-5cc9c023a5e1) technique to login to the corresponding web application.
An adversary may attempt to get detailed information about the operating system and hardware, including version, patches, hotfixes, service packs, and architecture. Adversaries may use the information from [System Information Discovery](https://app.tidalcyber.com/technique/a2961a00-450e-45a5-b293-f699d9f3b4ea) during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions.Tools such as [Systeminfo](https://app.tidalcyber.com/software/cecea681-a753-47b5-9d77-c10a5b4403ab) can be used to gather detailed system information. If running with privileged access, a breakdown of system data can be gathered through the systemsetup configuration tool on macOS. As an example, adversaries with user-level access can execute the df -aH command to obtain currently mounted disks and associated freely available space. Adversaries may also leverage a [Network Device CLI](https://app.tidalcyber.com/technique/284bfbb3-99f0-4c3d-bc1f-ab74065b7907) on network devices to gather detailed system information (e.g. show version).[[US-CERT-TA18-106A](https://app.tidalcyber.com/references/1fe55557-94af-4697-a675-884701f70f2a)] [System Information Discovery](https://app.tidalcyber.com/technique/a2961a00-450e-45a5-b293-f699d9f3b4ea) combined with information gathered from other forms of discovery and reconnaissance can drive payload development and concealment.[[OSX.FairyTale](https://app.tidalcyber.com/references/27f8ad45-53d2-48ba-b549-f7674cf9c2e7)][[20 macOS Common Tools and Techniques](https://app.tidalcyber.com/references/3ee99ff4-daf4-4776-9d94-f7cf193c2b0c)]Infrastructure as a Service (IaaS) cloud providers such as AWS, GCP, and Azure allow access to instance and virtual machine information via APIs. Successful authenticated API calls can return data such as the operating system platform and status of a particular instance or the model view of a virtual machine.[[Amazon Describe Instance](https://app.tidalcyber.com/references/c0b6a8a4-0d94-414d-b5ab-cf5485240dee)][[Google Instances Resource](https://app.tidalcyber.com/references/9733447c-072f-4da8-9cc7-0a0ce6a3b820)][[Microsoft Virutal Machine API](https://app.tidalcyber.com/references/f565c237-07c5-4e9e-9879-513627517109)]
