Authentication
Authenticate (or verify) the identities of users, processes, or devices, as a prerequisite to allowing access to organizational systems.
What an assessor scores, the objectives
IA.L2-3.5.2 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 identity of each user is authenticated or verified as a prerequisite to system access
- b.the identity of each process acting on behalf of a user is authenticated or verified as a prerequisite to system access
- c.the identity of each device accessing or connecting to the system is authenticated or verified as a prerequisite to system access
How a C3PAO checks it
NIST SP 800-171A defines three assessment methods. For IA.L2-3.5.2, an assessor uses these:
Identification and authentication policy; system security plan; procedures addressing authenticator management; procedures addressing user identification and authentication; system design documentation; list of system authenticator types; system configuration settings and associated documentation; change control records associated with managing system authenticators; system audit logs and records; other relevant documents or records
Personnel with authenticator management responsibilities; personnel with information security responsibilities; system or network administrators
Mechanisms supporting or implementing authenticator management capability
What it means, in context
Individual authenticators include the following: passwords, key cards, cryptographic devices, and one -time password devices. Initial authenticator content is the actual content of the authenticator, for example, the initial password. In contrast, the requirements about authenticator content include the minimum password length. Developers ship system components with factory default authentication credentials to allow for initial installation and configuration. Default authentication credentials are often well known, easily discoverable, and present a significant security risk. Systems support authenticator management by organization- defined settings and restrictions for various authenticator characteristics including minimum password length, validation time window for time s ynchronous one -time tokens, and number of allowed rejections during the verification stage of biometric authentication. Authenticator management includes issuing and revoking, when no longer needed, authenticators for temporary access such as that required for remote maintenance. Device authenticators include certificates and passwords. NIST SP 800-63-3 provides guidance on digital identities.
Before a person or device is given system access, verify that the user or device is who or what it claims to be. This verification is called authentication. The most common way to verify identity is using a username and a hard-to-guess password. Some devices ship with default usernames and passwords. Some devices ship with a default username (e.g., a dmin) and password. A default username and password must be immediately changed to something unique. Default passwords may be well known to the public, easily found in a search, or easy to guess, allowing an unauthorized person to access the system. Example 1 You are in charge of purchasing. You know that some laptops come with a default username and password. You notify IT that all default passwords should be reset prior to laptop use [a]. You ask IT to explain the importance of resetting default passwords and convey how easily they are discovered using internet searches during next week ’s cybersecurity awareness training. Example 2 Your company decides to use cloud services for email and other capabilities. Upon reviewing this requirement, you realize every user or device that connects to the cloud service must be authenticated. As a result, you work with your cloud service provider to ensure that only properly authenticated users and devices are allowed to connect to the system [a,c]. Potential Assessment Considerations • Are unique authenticators used to verify user identities (e.g., passwords) [a]? • An example of a process acting on behalf of users could be a script that logs in as a person or service account [b]. Can the OSA show that it maintains a record of all of those service accounts for use when reviewing log data or responding to an incident? • Are user credentials authenticated in system processes (e.g., credentials binding, certificates, tokens) [b]? • Are device identifiers used in authentication processes (e.g., MAC address, non- anonymous computer name, certificates) [c]?
What passing evidence looks like
Proof every path to CUI requires authentication before access: the sign in requirement itself, no anonymous shares, no passwordless local accounts.
Common ways contractors fail IA.L2-3.5.2
- !The anonymous file share is the classic failure: an open SMB share or an Anyone with the link works in the CUI library breaks this instantly. Audit link sharing before assessment.
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Prove IA.L2-3.5.2, and the other 109
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IA.L2-3.5.2 questions, answered
How many points is CMMC requirement IA.L2-3.5.2 worth?+
IA.L2-3.5.2 is worth 5 points in the CMMC Level 2 score under 32 CFR 170.24. If it is not met, you lose 5 from your total of 110.
Can IA.L2-3.5.2 be placed on a POA&M?+
No. IA.L2-3.5.2 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 IA.L2-3.5.2 belong to?+
IA.L2-3.5.2 is in the Identification & Authentication (IA) family, one of the 14 families of NIST SP 800-171 that make up CMMC Level 2.
- NIST SP 800-171 Rev. 2 3.5.2
- FAR Clause 52.204-21 b.1.vi