What is the most common gap auditors find on SI-10(5)?

Information inputs are accepted from untrusted sources or unapproved formats

NIST SP 800-53 Rev 5 · SI - System and Information Integrity

`SI-10(5)` Information Input Validation | Restrict Inputs to Trusted Sources and Approved Formats

Q: What evidence do auditors commonly ask for on SI-10(5) Information Input Validation | Restrict Inputs to Trusted Sources and Approved Formats?

System and information integrity policy; System and information integrity procedures; Procedures addressing information input validation; System design documentation; System configuration settings and associated documentation; List of trusted sources for information inputs.

Restrict the use of information inputs to organization-defined trusted sources and/or organization-defined formats.

Source: NIST SP 800-53 Rev 5, SI-10(5). The statement above is our statement of the clause, read from the published text and cited so you can check it against the official text, not the instrument verbatim. Open NIST SP 800-53 Rev 5 in the compliance library.

Base controls and their enhancements. Which apply follows the baseline you are assessed against (for example FedRAMP Moderate or High, or the low, moderate and high baselines of SP 800-53B). Text in square brackets is a parameter your organisation sets.

artefacts

held by a system

at each review

hard

to go live

Policy repository / GRC workspace

where the evidence lives

teal = a system already holds it · olive = produced at each review. To go live: easy when half or more of the artefacts are already held by a system, moderate from a quarter to a half, hard below a quarter.

These are the artefacts auditors commonly ask for on this requirement, our guidance rather than text from the standard. Your assessor decides what is sufficient in your context, and asks for samples across the period when a report covers one.

system holds itEvidence a system already holds

none for this control

periodic reviewEvidence produced at each review

System audit records · Policy repository / GRC workspace
Test of Organizational processes for restricting information inputs; automated mechanisms supporting and/or implementing restriction of information inputs · Document repository

governing documentDocuments that govern the control

System and information integrity policy · Policy repository / GRC workspace
System and information integrity procedures · Policy repository / GRC workspace
Procedures addressing information input validation · Policy repository / GRC workspace
System design documentation · Document repository
System configuration settings and associated documentation · Policy repository / GRC workspace
List of trusted sources for information inputs · Document repository
List of acceptable formats for input restrictions · Document repository
System security plan · Policy repository / GRC workspace

First move

No system holds this evidence for you: it is people and documents. Reminders and routing to the owner still save time. Put the document under version control with an owner and review date, and log each review as a record with reviewer and date.

Common gaps auditors find

Information inputs are accepted from untrusted sources or unapproved formats
The trusted sources and approved formats were never defined

Do this for your whole sheet

Paste the rows you run your controls from and get this mapping for every control at once, with the periodic-review ones flagged and a first move per row. No account for the first run.

Build my evidence sheet

SI-10(4) Information Input Validation | Timing Interactions · SI-10(6) Information Input Validation | Injection Prevention