System & File Scanning
Perform periodic scans of organizational systems and real-time scans of files from external sources as files are downloaded, opened, or executed.
What gets scored, the objectives
SI.L2-3.14.5 is met only when every one of these 3 objectives, from NIST SP 800-171A, is satisfied. A single missed objective makes the whole requirement not met.
- a.the frequency for malicious code scans is defined
- b.malicious code scans are performed with the defined frequency
- c.real-time malicious code scans of files from external sources as files are downloaded, opened, or executed are performed
How this is assessed
NIST SP 800-171A defines three assessment methods. For SI.L2-3.14.5, whoever assesses it, including your own team in a self assessment, uses these:
System and information integrity policy; configuration management policy and procedures; procedures addressing malicious code protection; malicious code protection mechanisms; records of malicious code protection updates; system security plan; system design documentation; system configuration settings and associated documentation; scan results from malicious code protection mechanisms; record of actions initiated by malicious code protection mechanisms in response to malicious code detection; system audit logs and records; other relevant documents or records
System or network administrators; personnel with information security responsibilities; personnel installing, configuring, and maintaining the system; personnel with responsibility for malicious code protection; personnel with configuration management responsibility
Organizational processes for employing, updating, and configuring malicious code protection mechanisms; organizational process for addressing false positives and resulting potential impact; mechanisms supporting or implementing malicious code protection mechanisms (including updates and configurations); mechanisms supporting or implementing malicious code scanning and subsequent actions
What it means, in context
Periodic scans of organizational systems and real-time scans of files from external sources can detect malicious code. Malicious code can be encoded in various formats (e.g., UUENCODE, Unicode), contained within compressed or hidden files, or hidden in files using techniques such as steganography. Malicious code can be inserted into systems in a variety of ways including web accesses, electronic mail, electronic mail attachments, and portable storage devices. Malicious code insertions occur through the exploitation of system vulnerabilities.
Use anti-malware software to scan for and identify viruses in your computer systems and determine how often scans are conducted. Real-time scans look at the system whenever new files are downloaded, opened, and saved. Periodic scans check previously saved files against updated malware information. Example You work with your company’s email provider to enable enhanced protections that will scan all attachments to identify and quarantine those that may be harmful prior to a user opening them [c]. In addition, you configure antivirus software on each computer to scan for malicious code every day [a,b]. The software also scans files that are downloaded or copied from removable media such as USB drives. It quarantines any suspicious files and notifies the security team [c].
What passing evidence looks like
Periodic full scans plus real time scanning of files from outside: both settings from the AV console and a recent scheduled scan result.
Common ways contractors fail SI.L2-3.14.5
- !Three objectives: the scan frequency written down, the scheduled periodic scan running at that frequency, AND real time protection on downloads and external files. Capture the stated frequency, both settings, and one completed scan log.
The step by step walkthrough for Microsoft 365 GCC High, Google Workspace, and on premises setups, plus the exact evidence to capture, lives inside the CMMC Level 2 plan.
Prove SI.L2-3.14.5, and the other 109
The Level 2 workspace walks your team through all 110 requirements at the objective level, drafts your SSP section by section from your own record for your team to read and accept, gives a prime or your own internal auditor a read only seat on the same record, and a credentialed officer reviews every step.
Book a free advisory callNo credit card, and Level 1 and Level 2 are both open, so sign up for the level your contracts call for. Self assessed and self attested: you score yourself in SPRS on a three year cycle and your senior official affirms it every year. As of September 3, 2026 a class deviation directs contracting officers to remove third party assessment from contracts. The program rule still provides for it, so your solicitation sets the track. Your team builds the same evidence either way. DFARS 252.204-7012 is unaffected, and the NIST SP 800-171 Rev 2 baseline is unchanged.
SI.L2-3.14.5 questions, answered
How many points is CMMC requirement SI.L2-3.14.5 worth?+
SI.L2-3.14.5 is worth 3 points in the CMMC Level 2 score under 32 CFR 170.24. If it is not met, you lose 3 from your total of 110.
Can SI.L2-3.14.5 be placed on a POA&M?+
No. SI.L2-3.14.5 must be fully met before you can file. It cannot be deferred to a POA&M, so it is a gate on your assessment.
What family does SI.L2-3.14.5 belong to?+
SI.L2-3.14.5 is in the System & Information Integrity (SI) family, one of the 14 families of NIST SP 800-171 that make up CMMC Level 2.
- NIST SP 800-171 Rev. 2 3.14.5
- FAR Clause 52.204-21 b.1.xv