type: attack-pattern
spec_version: 2.1
id: attack-pattern--6831414d-bb70-42b7-8030-d4e06b2660c9
created: 2020-01-30T14:11:41.212Z
created_by_ref: identity--c78cb6e5-0c4b-4611-8297-d1b8b55e40b5
revoked: no
external_references: source_name: mitre-attack
url: https://attack.mitre.org/techniques/T1548/001
external_id: T1548.001
source_name: GTFOBins Suid
description: Emilio Pinna, Andrea Cardaci. (n.d.). GTFOBins. Retrieved January 28, 2022.
url: https://gtfobins.github.io/#+suid
source_name: OSX Keydnap malware
description: Marc-Etienne M.Leveille. (2016, July 6). New OSX/Keydnap malware is hungry for credentials. Retrieved July 3, 2017.
url: https://www.welivesecurity.com/2016/07/06/new-osxkeydnap-malware-hungry-credentials/
source_name: setuid man page
description: Michael Kerrisk. (2017, September 15). Linux Programmer's Manual. Retrieved September 21, 2018.
url: http://man7.org/linux/man-pages/man2/setuid.2.html
object_marking_refs: marking-definition--fa42a846-8d90-4e51-bc29-71d5b4802168
modified: 2025-10-24T17:48:53.456Z
name: Setuid and Setgid
description: An adversary may abuse configurations where an application has the setuid or setgid bits set in order to get code running in a different (and possibly more privileged) user’s context. On Linux or macOS, when the setuid or setgid bits are set for an application binary, the application will run with the privileges of the owning user or group respectively.(Citation: setuid man page) Normally an application is run in the current user’s context, regardless of which user or group owns the application. However, there are instances where programs need to be executed in an elevated context to function properly, but the user running them may not have the specific required privileges.

Instead of creating an entry in the sudoers file, which must be done by root, any user can specify the setuid or setgid flag to be set for their own applications (i.e. [Linux and Mac File and Directory Permissions Modification](https://attack.mitre.org/techniques/T1222/002)). The chmod command can set these bits with bitmasking, chmod 4777 [file] or via shorthand naming, chmod u+s [file]. This will enable the setuid bit. To enable the setgid bit, chmod 2775 and chmod g+s can be used.

Adversaries can use this mechanism on their own malware to make sure they're able to execute in elevated contexts in the future.(Citation: OSX Keydnap malware) This abuse is often part of a "shell escape" or other actions to bypass an execution environment with restricted permissions.

Alternatively, adversaries may choose to find and target vulnerable binaries with the setuid or setgid bits already enabled (i.e. [File and Directory Discovery](https://attack.mitre.org/techniques/T1083)). The setuid and setguid bits are indicated with an "s" instead of an "x" when viewing a file's attributes via ls -l. The find command can also be used to search for such files. For example, find / -perm +4000 2>/dev/null can be used to find files with setuid set and find / -perm +2000 2>/dev/null may be used for setgid. Binaries that have these bits set may then be abused by adversaries.(Citation: GTFOBins Suid)
kill_chain_phases: kill_chain_name: mitre-attack
phase_name: privilege-escalation
kill_chain_name: mitre-attack
phase_name: defense-evasion
x_mitre_attack_spec_version: 3.2.0
x_mitre_deprecated: no
x_mitre_domains: enterprise-attack
x_mitre_is_subtechnique: yes
x_mitre_modified_by_ref: identity--c78cb6e5-0c4b-4611-8297-d1b8b55e40b5
x_mitre_platforms: Linux
macOS
x_mitre_version: 1.2