T1546.004: Unix Shell Configuration Modification
Adversaries may establish persistence through executing malicious commands triggered by a user’s shell. User Unix Shells execute several configuration scripts at different points throughout the session based on events. For example, when a user opens a command-line interface or remotely logs in (such as via SSH) a login shell is initiated. The login shell executes scripts from the system (/etc) and the user’s home directory (~/) to configure the environment. All login shells on a system use /etc/profile when initiated. These configuration scripts run at the permission level of their directory and are often used to set environment variables, create aliases, and customize the user’s environment. When the shell exits or terminates, additional shell scripts are executed to ensure the shell exits appropriately.
Adversaries may attempt to establish persistence by inserting commands into scripts automatically executed by shells. Using bash as an example, the default shell for most GNU/Linux systems, adversaries may add commands that launch malicious binaries into the /etc/profile and /etc/profile.d files.[1][2] These files typically require root permissions to modify and are executed each time any shell on a system launches. For user level permissions, adversaries can insert malicious commands into ~/.bash_profile, ~/.bash_login, or ~/.profile which are sourced when a user opens a command-line interface or connects remotely.[3][4] Since the system only executes the first existing file in the listed order, adversaries have used ~/.bash_profile to ensure execution. Adversaries have also leveraged the ~/.bashrc file which is additionally executed if the connection is established remotely or an additional interactive shell is opened, such as a new tab in the command-line interface.[5][3][6][7] Some malware targets the termination of a program to trigger execution, adversaries can use the ~/.bash_logout file to execute malicious commands at the end of a session.
For macOS, the functionality of this technique is similar but may leverage zsh, the default shell for macOS 10.15+. When the Terminal.app is opened, the application launches a zsh login shell and a zsh interactive shell. The login shell configures the system environment using /etc/profile, /etc/zshenv, /etc/zprofile, and /etc/zlogin.[8][9][10][11] The login shell then configures the user environment with ~/.zprofile and ~/.zlogin. The interactive shell uses the ~/.zshrc to configure the user environment. Upon exiting, /etc/zlogout and ~/.zlogout are executed. For legacy programs, macOS executes /etc/bashrc on startup.
Security context for executives and security teams
T1546.004: Unix Shell Configuration Modification describes Adversaries may establish persistence through executing malicious commands triggered by a user’s shell. User [Unix Shell](https://attack.mitre.org/techniques/T1059/004)s execute several configuration scripts at different points throughout the session based on events. For example, when a user opens a command-line interface or remotely logs in (such as via SSH) a login shell is initiated. The login shell executes scripts from the system ( /etc ) and the user’s home directory ( ~/ ) to configure the environment. All l...
Executive priority
T1546.004: Unix Shell Configuration Modification is an official MITRE ATT&CK technique. Glexia treats it as defensive behavior context for prioritizing monitoring, control validation, and response planning without using the object by itself as an attribution claim.
Technical view
Security teams should validate T1546.004: Unix Shell Configuration Modification by reviewing the official ATT&CK relationships, mapped tactics (privilege-escalation, persistence), supported platforms (Linux, macOS), and available local telemetry before making detection or mitigation decisions.
Likely telemetry
- Official ATT&CK relationships and object metadata
- Identity, privilege, and authentication events
- Network, endpoint, and security-tool telemetry
Detection direction
- Validate whether T1546.004: Unix Shell Configuration Modification appears in your detection coverage and tabletop scenarios.
- Use the object to align executive risk language with SOC, incident response, and detection engineering work.
- Do not treat ATT&CK relationship context as attribution without corroborating evidence.
Mitigation priorities
- Map the object to existing controls and identify missing telemetry or response ownership.
- Prioritize mitigations that reduce exposure on the listed platforms and tactics.
- Review adjacent ATT&CK relationships before changing policy, detections, or reporting language.
Additional notes and limits
Baseline Glexia take generated from the official MITRE ATT&CK STIX object, source hash, tactics, platforms, and detection fields. It is safe to replace with a richer model-generated take for the same source hash later.
This baseline take is source-grounded and schema-validated, but it does not include environment-specific telemetry, incident evidence, or threat-intelligence corroboration.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Unix Shell Configuration Modification
Adversaries may establish persistence through executing malicious commands triggered by a user’s shell. User Unix Shells execute several configuration scripts at different points throughout the session based on events. For example, when a user opens a command-line interface or remotely logs in (such as via SSH) a login shell is initiated. The login shell executes scripts from the system (/etc) and the user’s home directory (~/) to configure the environment. All login shells on a system use /etc/profile when initiated. These configuration scripts run at the permission level of their directory and are often used to set environment variables, create aliases, and customize the user’s environment. When the shell exits or terminates, additional shell scripts are executed to ensure the shell exits appropriately.
Adversaries may attempt to establish persistence by inserting commands into scripts automatically executed by shells. Using bash as an example, the default shell for most GNU/Linux systems, adversaries may add commands that launch malicious binaries into the /etc/profile and /etc/profile.d files.[1][2] These files typically require root permissions to modify and are executed each time any shell on a system launches. For user level permissions, adversaries can insert malicious commands into ~/.bash_profile, ~/.bash_login, or ~/.profile which are sourced when a user opens a command-line interface or connects remotely.[3][4] Since the system only executes the first existing file in the listed order, adversaries have used ~/.bash_profile to ensure execution. Adversaries have also leveraged the ~/.bashrc file which is additionally executed if the connection is established remotely or an additional interactive shell is opened, such as a new tab in the command-line interface.[5][3][6][7] Some malware targets the termination of a program to trigger execution, adversaries can use the ~/.bash_logout file to execute malicious commands at the end of a session.
For macOS, the functionality of this technique is similar but may leverage zsh, the default shell for macOS 10.15+. When the Terminal.app is opened, the application launches a zsh login shell and a zsh interactive shell. The login shell configures the system environment using /etc/profile, /etc/zshenv, /etc/zprofile, and /etc/zlogin.[8][9][10][11] The login shell then configures the user environment with ~/.zprofile and ~/.zlogin. The interactive shell uses the ~/.zshrc to configure the user environment. Upon exiting, /etc/zlogout and ~/.zlogout are executed. For legacy programs, macOS executes /etc/bashrc on startup.
How security teams should use this page
Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.
Related techniques
This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.
| Domain | ID | Name | Relationship / procedure |
|---|---|---|---|
| Enterprise | T1156 | Malicious Shell Modification | Malicious Shell Modification revoked by this object. |
| Enterprise | T1546 | Event Triggered Execution | This object subtechnique of Event Triggered Execution. |
Groups, software, and campaigns
G1052: Contagious Interview
Contagious Interview is a North Korea–aligned threat group active since 2023. The group conducts both cyberespionage and financially motivated operations, including the theft of cryptocurrency and user credentials. Contagious Interview targets Windows, Linux, and macOS systems, with a particular focus on individuals engaged in software development and cryptocurrency-related activities. [1][2][3][4][5][6][7][8]
S1078: RotaJakiro
RotaJakiro is a 64-bit Linux backdoor used by APT32. First seen in 2018, it uses a plugin architecture to extend capabilities. RotaJakiro can determine it's permission level and execute according to access type (`root` or `user`).[1][2]
S0362: Linux Rabbit
Linux Rabbit is malware that targeted Linux servers and IoT devices in a campaign lasting from August to October 2018. It shares code with another strain of malware known as Rabbot. The goal of the campaign was to install cryptocurrency miners onto the targeted servers and devices.[1]
S0690: Green Lambert
Green Lambert is a modular backdoor that security researchers assess has been used by an advanced threat group referred to as Longhorn and The Lamberts. First reported in 2017, the Windows variant of Green Lambert may have been used as early as 2008; a macOS version was uploaded to a multiscanner service in September 2014.[1][2]
S9014: PHASEJAM
S0658: XCSSET
XCSSET is a modular macOS malware family delivered through infected Xcode projects and executed when the project is compiled. Active since August 2020, it has been observed installing backdoors, spoofed browsers, collecting data, and encrypting user files. It is composed of SHC-compiled shell scripts and run-only AppleScripts, often hiding in apps that mimic system tools (such as Xcode, Mail, or Notes) or use familiar icons (like Launchpad) to avoid detection.[1][2][3]
C0045: ShadowRay
ShadowRay was a campaign that began in late 2023 targeting the education, cryptocurrency, biopharma, and other sectors through a vulnerability (CVE-2023-48022) in the Ray AI framework named ShadowRay. According to security researchers ShadowRay was the first known instance of AI workloads being activley exploited in the wild through vulnerabilities in AI infrastructure. CVE-2023-48022, which allows access to compute resources and sensitive data for exposed instances, remains unpatched and has been disputed by the vendor as they maintain that Ray is not intended for use outside of a strictly controlled network environment.[1]
All related ATT&CK context
Mitigation direction
Object version and sync metadata
The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates.
Imported snapshots across ATT&CK releases(3)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 20.0 | 2.2 | Older bundle | 1084ba9fecfe… | ||
| 19.2 | 2.2 | Current bundle | 1084ba9fecfe… | ||
| 19.1 | 2.2 | Older bundle | 1084ba9fecfe… |
Mirrored ATT&CK source object
The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.
External references and citations
MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.
- [1]intezer-kaiji-malware
Paul Litvak. (2020, May 4). Kaiji: New Chinese Linux malware turning to Golang. Retrieved December 17, 2020.
Open source URL - [2]bencane blog bashrc
Benjamin Cane. (2013, September 16). Understanding a little more about /etc/profile and /etc/bashrc. Retrieved September 25, 2024.
Open source URL - [3]anomali-rocke-tactics
Anomali Threat Research. (2019, October 15). Illicit Cryptomining Threat Actor Rocke Changes Tactics, Now More Difficult to Detect. Retrieved December 17, 2020.
Open source URL - [4]Linux manual bash invocation
ArchWiki. (2021, January 19). Bash. Retrieved February 25, 2021.
Open source URL - [5]Tsunami
Claud Xiao and Cong Zheng. (2017, April 6). New IoT/Linux Malware Targets DVRs, Forms Botnet. Retrieved December 17, 2020.
Open source URL - [6]anomali-linux-rabbit
Anomali Threat Research. (2018, December 6). Pulling Linux Rabbit/Rabbot Malware Out of a Hat. Retrieved December 17, 2020.
Open source URL - [7]Magento
Cesar Anjos. (2018, May 31). Shell Logins as a Magento Reinfection Vector. Retrieved December 17, 2020.
Open source URL - [8]ScriptingOSX zsh
Armin Briegel. (2019, June 5). Moving to zsh, part 2: Configuration Files. Retrieved February 25, 2021.
Open source URL - [9]PersistentJXA_leopitt
Leo Pitt. (2020, August 6). Persistent JXA - A poor man's Powershell for macOS. Retrieved January 11, 2021.
Open source URL - [10]code_persistence_zsh
Leo Pitt. (2020, November 11). Github - PersistentJXA/BashProfilePersist.js. Retrieved January 11, 2021.
Open source URL - [11]macOS MS office sandbox escape
Cedric Owens. (2021, May 22). macOS MS Office Sandbox Brain Dump. Retrieved August 20, 2021.
Open source URL - [12]ESF_filemonitor
Patrick Wardle. (2019, September 17). Writing a File Monitor with Apple's Endpoint Security Framework. Retrieved December 17, 2020.
Open source URL - [13]mitre-attackT1546.004Open source URL
Source: MITRE ATT&CK®. © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. MITRE ATT&CK and ATT&CK are registered trademarks of The MITRE Corporation. Glexia is not affiliated with or endorsed by MITRE.