getfacl
Also called: get file access control list
Course: AP® Cybersecurity Shows up in: Unit 5: Securing Applications and Data
The Linux command that shows a file's extended access control list (ACL), the extra permissions marked by a + at the end of `ls -l` output.
Appears in the course and exam description (CED): 5.2.D.4
Why it matters in Unit 5
A + after the permission string means ls -l is not the whole story; run getfacl to see who else has access.
Example
ls -l shows -rw-r-----+ 1 maya finance 18432 Nov 3 09:12 budget.xlsx, and getfacl budget.xlsx reveals one extra user with read access.
Go deeper: the professional references
Security professionals worldwide use these: the NIST glossary (the U.S. government's official security dictionary), MITRE ATT&CK (real attacker techniques), MITRE CWE (software weaknesses) and the internet's own standards (RFCs). They go beyond the AP® course, so use the definition above for the exam.