T1556.003 Pluggable Authentication Modules
sub-techniqueEnterpriseAdversaries may modify pluggable authentication modules (PAM) to access user credentials or enable otherwise unwarranted access to accounts. PAM is a modular system of configuration files, libraries, and executable files which guide authentication for many services. The most common authentication module is <code>pam_unix.so</code>, which retrieves, sets, and verifies account authentication information in <code>/etc/passwd</code> and <code>/etc/shadow</code>. Adversaries may modify components of the PAM system to create backdoors. PAM components, such as <code>pam_unix.so</code>, can be patched to accept arbitrary adversary supplied values as legitimate credentials. Malicious modifications to the PAM system may also be abused to steal credentials. Adversaries may infect PAM resources with code to harvest user credentials, since the values exchanged with PAM components may be plain-text since PAM does not store passwords.
platforms
Platforms this applies to.
tactics
ATT&CK tactics this technique serves.
sub-technique of
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mitigations
ATT&CK mitigations that reduce this.
detected by (3)
Data components that detect this.
countered by (D3FEND)
D3FEND countermeasures that counter this.
Detect
Isolate
Deceive
Restore
NIST CSF 2.0 — areas of relevance (Protect / Detect)
NIST CSF 2.0 areas this most relates to (evidence-ranked).
- PR.AAIdentity Management, Authentication, and Access Controlstrong · backed by 7 of 12 mapped controls
- DE.CMContinuous Monitoringmoderate · backed by 4 of 12 mapped controls
- PR.DSData Securitymoderate · backed by 4 of 12 mapped controls
Derived from MITRE CTID (Apache-2.0) and the NIST 800-53 ↔ CSF crosswalk (public domain). Indicative relevance along the Protect/Detect axis — not a compliance assessment or coverage claim.
mitigating controls (12)
Security controls that mitigate this.
software (2)
Malware and tools associated with this.
source
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