SI.L2-3.14.3 Security alerts and advisories: evidence and cost

What SI.L2-3.14.3 security alerts and advisories requires

If you are preparing for a CMMC Level 2 assessment, treat SI.L2-3.14.3 as a requirement that must be MET, not one you can carry on a plan of action and milestones. It is worth 5 points, and under the scoring methodology a NOT MET result subtracts those points from the maximum of 110. Because it is worth more than 1 point, it cannot go on a POA&M, so an unmet result keeps the organization from reaching Conditional or Final Level 2 status. The requirement is the Level 2 version of NIST SP 800-171 Rev. 2 requirement 3.14.3, a basic requirement in the System and Information Integrity family.

In plain terms, the requirement asks for three things. First, a defined way to receive security alerts and advisories from relevant external sources, such as vendors, government advisory services and information sharing communities. Second, defined response actions that someone is responsible for carrying out when an alert affects your systems. Third, records showing that both happened. The risk it addresses is simple: a published vulnerability or active campaign can sit in an inbox for weeks while the affected system stays exposed. NIST SP 800-171A splits the requirement into three assessment objectives covering response actions, monitoring of alerts and advisories, and action taken in response, so an assessor will look for all three.

This is hard to get right because no single tool does it. A feed aggregator, a ticketing system and a patch process each cover part of the chain, and ownership often falls between security operations, IT and the system owner. Before the assessment, confirm who subscribes to each source, who triages incoming alerts, who decides the response, and where the decision is recorded. Ask an assessor's guidance or your Registered Practitioner Organization to show you what evidence of receipt and action they expect, and keep records in final form, since drafts do not count toward a MET result.

Which alert sources, teams and tools fall in scope for security alerts

Scoping for SI.L2-3.14.3 starts with the question of which systems inside the CUI boundary generate alerts, which outside sources must reach your team, and who acts on them. Each card below is a decision that changes how much monitoring, distribution and record keeping the assessor will expect you to show.

Boundary systems that need alert coverage

Start from the system security plan and list every asset that stores, processes or transmits CUI, plus the components that protect it. Operating systems, firewalls, endpoints, identity services and cloud tenants each publish their own advisories. Record which product, version and vendor channel covers each asset. An alert source that is not tied to an in-scope asset is hard to justify, and an in-scope asset with no source is a gap the assessor will find.

Vendor and product security notices

Vendor security bulletins are usually the most direct source for the products you run. Decide which vendors belong on the list, who subscribes to each notice, and whether the subscription goes to a shared mailbox, a ticketing queue or a person. Confirm that the vendor notice channels you rely on are still active for your versions, because end-of-support products often stop publishing useful advisories.

External CERTs and government advisories

National and sector computer emergency response teams publish advisories that cover threats across many products and vendors. The CMMC Assessment Guide Level 2 lists email distributions, RSS feeds and meetings as ways to receive alerts. Decide which government or CERT feeds you will monitor, and document why each one was chosen for your environment and contracts.

Sector sharing groups and information sharing

Industry information sharing groups pass along threat context that vendors and CERTs may not cover, especially for defense supply chains. Membership terms, distribution rules and handling restrictions differ by group. Confirm which groups you belong to, who receives their traffic, and whether any shared material must be controlled as CUI or as proprietary information before it reaches a wider team.

Internal teams and on-call responders

An alert only satisfies the requirement if someone takes a documented action on it. Name the security, IT and engineering roles that receive each category of alert, the time they are expected to review it and the response steps they follow. Assessors interview these people, so their roles, backups and handoffs need to match what the procedure says.

Managed providers and cloud providers in the chain

When an MSP, managed security provider or cloud provider operates part of the environment, it may receive the alerts for those systems first. Decide whether it acts on your behalf, reports to you, or only forwards notices. Put the responsibilities in writing, confirm that its alert records can be produced for your assessment, and confirm which evidence sits with it and which sits with you.

How an assessor tests security alerts and advisories

This table maps the three NIST SP 800-171A assessment objectives for SI.L2-3.14.3 to the test approach, evidence an assessor requests and findings that commonly cause a NOT MET result. Read it as a checklist for building proof that alerts are received, passed to the right people and acted on, since a 5-point requirement cannot go on a POA&M.

Assessment area	What the assessor tests	Evidence requested and common findings
Identify response actions	Whether the organization has defined what it does when an alert or advisory arrives, including who decides, who acts and how fast	Written procedure or runbook naming owners and steps. Finding: a procedure exists but no one can describe it during interviews
Monitor alerts and advisories	Whether the organization subscribes to relevant external sources and reviews them on a schedule that matches how often alerts arrive	Subscription list, mailing list or feed configuration, and review logs. Finding: subscriptions lapsed or were set up by one person who has left
Take action in response	Whether alerts are triaged, applied to affected assets and closed with a documented outcome	Tickets or entries showing the alert, the affected systems, the action taken and the closure. Finding: alerts are read but no record shows what changed
Interviews with recipients	Whether people who receive alerts understand their role and can explain the process in their own words	Short interviews with system administrators, security staff and the person who owns the procedure. Finding: answers differ from the written process
Interviews with external organizations	Whether outside sources such as vendors, information sharing groups or government advisory services are identified and used	Named sources, contact or subscription records, and any sharing agreements. Finding: sources are assumed rather than documented
Test of receipt and dissemination	Whether alerts reach the intended recipients through the channels the organization defined	Sample alert traced from source to recipient, including distribution lists and feed settings. Finding: distribution lists omit current staff
Test of action on alerts	Whether a sample of alerts shows actions taken on relevant systems, not only acknowledgment	Sample of recent advisories matched to affected assets and remediation or risk acceptance records. Finding: no link between advisory and asset inventory
Records of alerts and advisories	Whether records are kept in a form that can be reviewed later, including the final version of each record	Retained alert log, dated entries and final closure notes. Finding: records exist only as drafts or as unsaved email threads

Steps to build an alert intake and response process

This sequence turns a scattered stream of vendor bulletins, government advisories and tool notifications into a defined intake channel, a triage method and a dated record of what was received and done, which is what an assessor will ask to see for SI.L2-3.14.3.

Name the sources and receiving roles
List every external source that applies to your systems, such as operating system and application vendors, network device makers, cloud providers, the US-CERT and CISA advisory feeds, and any sector information sharing body your contracts require. For each source, name a primary and backup role that receives it, such as a security operations lead or a system administrator for each platform. Output: a written source register with owner and backup for each entry, approved by the security lead. Confirm the authoritative feed list with your own environment inventory, since the sources that matter depend on what you run.
Set up intake channels for each source
Connect each source to a channel that the named role actually watches. The CMMC Assessment Guide Level 2 lists email distributions, RSS feeds and meetings as ways to receive alerts. A threat intelligence platform such as OpenCTI can ingest TAXII, RSS, CSV and JSON feeds, and MISP can hold and share indicators, but a platform is optional. Choose the channel by source volume and staff capacity. Output: a channel map showing where each source lands, plus a test alert that proves delivery reaches the named owner.
Define response actions for each alert type
Write the actions the organization takes for each category of alert, such as confirming whether an affected product is in the environment, applying a vendor fix, applying a compensating control, escalating to incident response, or closing the alert as not applicable. SP 800-171A treats identifying response actions as its own assessment objective, so the actions must be documented before they are needed. Output: a response procedure that names the action, the owner and the record that each action produces. Have the procedure approved and version controlled.
Set triage thresholds and escalation rules
Define how an alert is judged relevant and how urgent it is. Typical inputs are whether the product or version is in your inventory, whether the alert describes active exploitation, and whether the affected system holds CUI. Tie the highest-urgency category to escalation into the incident response process so that the same alert is not handled twice under different procedures. Output: a written triage matrix with a documented rule for each category, and a sample decision traced through it for a hypothetical alert labeled as illustrative.
Set a review cadence that matches alert volume
Schedule regular reviews of the intake channels and the open alert queue, and adjust the frequency to how often alerts actually arrive. The Assessment Guide expects reviews to keep pace with alert volume, so a busy feed needs more frequent review than a quiet one. Record the cadence and the reviewer in the procedure. Output: a review calendar and a log of completed reviews, including reviews where no new alerts arrived. Ask your assessor or consultant to confirm the cadence against your volume before the assessment.
Record each alert with its disposition
For every alert, record the source, the date received, the affected products, the triage decision, the actions taken, the person responsible and the closure date and reason. Evidence is only accepted in final form, so keep the record complete and do not leave entries in draft. A ticketing system or a findings tracker such as DefectDojo can hold these records, and it can import findings from many scanner report formats. Output: an alert register where every item has a closed disposition or a tracked open action.
Verify the process with a periodic check
Sample a set of recorded alerts and trace each one from source to disposition. Confirm the named role received the alert, the triage rule was applied, the response action happened and the record is complete. Fix gaps in the procedure or the channels and keep the check results as evidence. Output: a dated verification report that lists findings and corrections, which shows the process operates as written rather than only existing on paper.

How alert monitoring fits into a daily operating rhythm

The point of this section is that SI.L2-3.14.3 is met by a routine that runs every working day, not by a subscription. The CMMC Assessment Guide for Level 2 gives examples of how alerts reach an organization, including email distributions, RSS feeds and meetings. Those channels only count once they feed a named person's daily work. Start by writing down which feeds your organization subscribes to, who receives each one, and where the alert is first recorded. An assessor will ask the same question in interviews: who receives the advisory, and what happens next?

The Assessment Guide says review frequency should keep pace with how often alerts arrive. Nothing in the supplied facts sets a number of hours or days, so the reader should confirm the cadence with their own volume of advisories and document it in the procedure. A high-volume vendor feed may need a daily triage, while a quiet distribution may be reviewed in a weekly meeting. The practical test is simple: pull the last quarter's alert records and check whether the gap between receipt and review matches the cadence written in the procedure. Where it does not, either the procedure or the staffing needs to change.

Every alert that needs action should become a ticket with an owner, a due date set by the organization's own rules, and a closure reason. The response can be a patch, a configuration change, a compensating control, or a documented risk acceptance signed by someone with authority to accept it. Keep a record that links the advisory to the ticket and to the final evidence, such as a change record or a scan showing the fix. Tools such as OpenCTI can hold advisory and threat intelligence content, and DefectDojo can track findings through remediation, but the reader should confirm how each tool handles the link to the response record in their own environment. The assessor needs to trace one alert from receipt to closure, and a gap in that chain is the most common reason this requirement is not met.

Evidence that passes for security alerts and advisories

Assessors test SI.L2-3.14.3 by tracing a path: which sources feed alerts in, how they reach the people responsible, and what happened next. The cards below cover the records that show each step, and each one must exist in final form at assessment time.

Alert source register

A maintained list of every external source the organization relies on for security alerts and advisories, including vendor security bulletins, the CISA and US-CERT feeds your environment depends on, and any sector information sharing channels. For each source, record the owner, the products it covers and the review cadence. Assessors use this register to decide whether monitoring is scoped to the systems that matter. Confirm that every product in the CUI boundary appears against at least one source.

Distribution lists and subscriptions

Proof that alerts actually arrive: mailing list membership, vendor notification subscriptions, RSS or feed configurations and meeting invitations. The CMMC Assessment Guide cites email distributions, RSS feeds and meetings as acceptable channels. Export the subscriber list with dates added, and show that role-based mailboxes are monitored by named people rather than a departed employee's inbox.

Records of received alerts

Dated entries showing each alert or advisory received, its source, the affected product and the recipient. A ticket queue, a threat intelligence platform entry or a tagged mailbox folder can serve. Assessors look for a consistent record format and gaps in dates. If your team receives a high volume, keep an index that links each alert to its triage outcome so the trail stays searchable.

Triage and response tickets

Tickets that show how each relevant alert was assessed, who decided whether it applied, and what response was chosen, such as patching, a compensating control or a documented risk acceptance. Each ticket should close with a result and a date. This is where the defined response actions required by the requirement become visible, so write the response procedure before the first alert arrives.

Evidence of action taken

Proof that the response happened: change records, patch deployment reports, configuration exports, or scan results confirming the fix. Link each action back to the originating alert. Assessors test whether the action was taken, not just planned, so screenshots or exports dated after the alert are stronger than a statement that work is in progress.

Meeting minutes and review records

Minutes from security review meetings and periodic reviews of the source register and open alerts, showing attendees, decisions and follow-up owners. Reviews should keep pace with alert volume, so the review frequency you record must match what the tickets show. Finalize minutes and sign them off before an assessment; draft minutes do not count toward a MET determination.

Open-source tools that produce alert and response evidence

MISP is an open-source threat intelligence sharing platform licensed under AGPL-3.0-only. It is useful where your organization receives indicators from external sources and needs to record which indicators were seen in its own environment. Its records are the kind of evidence an assessor can check against the 3.14.3 objectives for monitoring alerts and taking action.

Indicator correlation: MISP matches indicators by exact value and by advanced patterns such as fuzzy hashes and CIDR overlaps, so an advisory's indicators can be tested against your logs.
Sightings: Recording a sighting documents that an indicator was observed, which supports the claim that alerts were acted on.
Sharing groups: Granular distribution controls limit which events go to which partners and between MISP instances.
Export formats: The REST API exports to STIX 1 and 2, CSV and Suricata, Snort and Zeek rule formats for downstream tools.

Confirm the license terms with counsel before you modify or host MISP for external users, and confirm which feeds your sources provide in a format MISP ingests.

What meeting SI.L2-3.14.3 costs in money and effort

This table breaks down the cost components of meeting SI.L2-3.14.3 by who is paid, whether the cost is one-time or recurring, and what drives it up or down. Use it to build a quote request that separates tooling from people, and to see where open-source tooling removes license spend but not operating effort.

Cost component	Who is paid or who carries it	One-time or recurring	What drives it, and what to ask for in a quote
Tooling and licenses	Vendor for commercial feeds or alert services, if chosen	Recurring	Open-source platforms such as MISP, OpenCTI and DefectDojo carry no license fee, so ask whether any commercial feed or subscription is included.
Hosting and infrastructure	Your cloud or data center provider, or the implementation partner for setup	Recurring	Feed volume, retention and the number of users. Ask for hosting sizing and whether it sits inside your CUI boundary.
Engineering to build intake and integrations	Implementation partner or internal platform engineers	One-time, with later changes	Number of sources (vendor advisories, CISA-style feeds, sector sharing groups), format conversions and ticketing links. Ask for a fixed-scope list of feeds and integrations.
Analyst time for triage and response	Your security staff, or a managed service if you buy one	Recurring	Alert volume and how many alerts apply to your products. Ask how the quote estimates triage effort and who owns the response decision.
Evidence upkeep	Your compliance lead, with partner support if contracted	Recurring	Review cadence, which the CMMC Assessment Guide ties to alert arrival rates. Ask for the records template and the review schedule included in scope.
Testing and external review	Independent reviewer or internal audit, if you request one	Periodic	How often you test that alerts reach the right people and get acted on. Confirm whether the partner's readiness work includes a pre-assessment review.
Assessor effort	The C3PAO or assessor, paid by you under its own engagement terms	Per assessment	Amount of evidence presented in final form and how many interviews are needed. Ask the assessor for its fee basis in writing before you commit.

Who does what: your team, a partner and the assessor

Your organization owns SI.L2-3.14.3. Your security function decides which external sources matter for your systems, who receives each alert, how urgent items are triaged, and what action is taken in response. Those decisions are the requirement, so they cannot be delegated to a vendor or consultant. Your people also sign off on the records that show alerts were received and acted on.

Source selection: Choose the advisory feeds, vendor bulletins, CISA products and sector information sharing channels that apply to your products and environment, and record why each one was chosen.
Triage and ownership: Name the role that reviews each alert and the role that decides on action, including who is covered when people are away.
Response decisions: Decide what happens to an alert that affects you, such as patching, compensating controls, configuration changes or a documented decision that the alert does not apply.
Review cadence: Set how often the alert queue is reviewed, matching the volume of alerts you actually receive, as the CMMC Assessment Guide expects.
Final records: Keep closed-out records in final form, not drafts, because assessors test only completed evidence.

Before assessment, confirm that every source, owner and response step has a named person and a dated record of use.

Where alert and advisory programs usually fall short

Most SI.L2-3.14.3 findings are not about missing tools. They come from programs that never wrote down their sources, depended on one person, or left no record of what was done with an alert. Each card below names a gap an assessor is likely to probe and the step that closes it.

No defined list of sources

A program that monitors whatever arrives in someone's inbox cannot show which external sources it relies on. Assessors look for a documented list of the alert and advisory sources the organization monitors, tied to the products and services in scope, such as the vendors of operating systems, firewalls and key applications, plus relevant government and industry feeds. Close the gap by writing the list into the system security plan, assigning an owner to each source, and recording how each one is received, whether by email distribution, RSS feed or vendor portal.

Single-person alert intake

When one engineer receives every advisory, the process stops during leave, reassignment or turnover, and the assessor sees no evidence that alerts are disseminated to the people who act on them. Interviews with recipients are a standard test for this requirement. Close the gap by routing each source to a shared distribution list or ticket queue, naming a primary and a backup for each role, and confirming that the backup has access and has actually received alerts.

No record of disposition

Receiving an advisory is not enough. For each alert, the organization should be able to show whether it applies to its environment, what action was taken, or why no action was needed. A log that lists alerts without outcomes gives the assessor nothing to test against the requirement's response objectives. Close the gap by recording, for every alert, the date received, the affected assets, the decision and the person who made it.

Responses not tied to a ticket

Actions taken on an advisory often happen in chat, email or someone's memory, so the trail from alert to fix cannot be followed. Assessors need to see that the response was taken and that it was tracked. Close the gap by opening a ticket for every alert that requires action, linking the advisory identifier to the change or patch record, and closing the ticket only after the fix or risk acceptance is documented. Open-source tools such as DefectDojo can hold findings that come from advisories alongside scanner output.

Review cadence that does not match volume

A weekly review of a feed that delivers alerts daily leaves gaps that an assessor will notice in the timestamps. The CMMC Assessment Guide expects review frequency to keep pace with how often alerts arrive. Close the gap by measuring alert volume over a representative period, setting the review schedule from that measurement, and noting in the procedure what happens to urgent alerts between scheduled reviews. Confirm the cadence with the assessor's guidance before relying on it.

Drafts presented as evidence

Procedures, source lists and alert logs that exist only as drafts, or that were written after the assessment was announced, will not satisfy the requirement. Assessors accept evidence only in final form. Close the gap by placing the procedure, source list and log under version control with approval dates and owners, and by keeping historical records of alerts as they were received rather than reconstructing them later.

Questions buyers ask about SI.L2-3.14.3

How much effort does monitoring security alerts and advisories take?

The effort is mostly recurring staff time rather than a large one-time build. The requirement asks you to receive alerts from relevant external sources, decide which ones matter to your environment, act on them, and keep records. Effort rises with the number of sources you subscribe to, how many systems you run, and how quickly your team must triage each advisory. The CMMC Assessment Guide notes that review cadence should keep pace with how often alerts arrive, so a quiet environment needs less time than one receiving many notices. Ask any provider to break the quote into a one-time setup of distribution lists, feeds and tickets, and a recurring triage and reporting workload.

Can we meet SI.L2-3.14.3 in-house?

Yes, in principle. The organization owns its controls, and nothing in the requirement requires an outside firm. What matters is whether you can show the three assessment objectives in SP 800-171A: identifying response actions, monitoring alerts and advisories, and taking action in response. A small team can do this with a defined distribution list, a written response procedure and a simple ticket queue. Outside help is usually most useful for preparing the tooling, writing the procedure and testing that records are complete. An independent assessor, not a consultant, decides whether the requirement is MET.

What skills and staff does this requirement need?

You need someone accountable for security operations who can read vendor and government advisories, judge whether each one affects your systems, and assign the fix. Engineers who manage the affected systems must be able to apply or document mitigations. Records need a clear owner so that every alert has a timestamp, a decision and an outcome. Leaders should approve the response procedure and review trends. Where the organization handles CUI, the people who receive alerts should be the same people who can act on them, and their roles should appear in the written procedure so an assessor can interview them.

How long does it usually take to set this up?

Setup time depends on how many systems you run, whether alert sources are already subscribed, and whether a ticketing process already exists. In general terms, the distribution lists and feeds are quick to establish, while the written response procedure, role assignments and first round of recorded alerts take longer because they need review and practice. Your timeline should also allow for evidence to accumulate, since an assessor looks for records over a period rather than a single set of notices. Confirm a schedule with any provider against your written scope, because this document does not state a duration.

Are open-source tools enough to meet this requirement?

Open-source tools can cover much of the workflow, but they do not replace the process. Platforms such as MISP and OpenCTI can ingest threat intelligence through feeds, TAXII and CSV or JSON files, correlate indicators, and keep a record of sightings. DefectDojo can import findings from more than 500 security tool report formats and deduplicate them, which helps track remediation. Greenbone Community Edition handles vulnerability scanning and stores results. The gap is usually the human layer: the procedure, the decisions and the proof that each advisory was reviewed and acted on. Confirm with each vendor which feed types and export formats your environment needs before you rely on them.

What does the current CMMC phase status mean for our timing?

The Department of War suspended CMMC Phase II on 13 July 2026, and that suspension was scheduled to pause the start of the Level 2 certification requirement that had been set for 10 November 2026. Phase I self-assessments, SPRS postings, annual affirmations and DFARS 252.204-7012 obligations remain in place. The DoW CIO About CMMC page states that implementation is paused in Phase 1 and may only require self-assessments at Levels 1 and 2. Because the eCFR text still shows the original schedule, confirm the current requirement with your contracting officer before setting deadlines. Regardless of timing, SI.L2-3.14.3 is worth 5 points and must be MET, not placed on a POA&M, so building the capability early remains sensible.

How the current CMMC phase status affects planning

The most important planning point for SI.L2-3.14.3 is that the Level 2 certification timeline has moved, but the obligations that already apply have not. On 13 July 2026 the Department of War suspended CMMC Phase II, which had been scheduled to start 10 November 2026 and would have required Level 2 C3PAO certification for applicable contracts. A 60-day review by a CMMC Reform Task Force followed. Phase I self-assessments, SPRS postings, annual affirmations and DFARS 252.204-7012 obligations remain in place. A contractor that handles CUI should therefore treat its alert monitoring process as a live obligation today, even though a third-party assessment is not currently required on the original schedule.

The published schedules also disagree. The eCFR text of 32 CFR 170.3(e) still contains the original four-phase schedule, while the DoW CIO "About CMMC" page, as of 17 October 2026, describes implementation as paused in Phase 1 and says it may only require self-assessments at Levels 1 and 2. Where the two conflict, the Department's current statements govern what is being enforced, but you should not rely on a secondary summary. Check the DoW CIO About CMMC page and the rule text yourself, record the date you checked, and file that record with your System Security Plan. Because SI.L2-3.14.3 is worth 5 points and cannot be placed on a POA&M, its status will count against your score under any schedule that uses self-assessment.

Confirm three things with your contracting officer before you finalize your plan: which CMMC level and assessment type each active contract or solicitation requires, whether any Phase I self-assessment or affirmation applies to you now, and whether your prime contractor has flowed down any CMMC requirement to you. Ask for the answer in writing. Then build your alert monitoring to the Level 2 standard regardless of the schedule, since the requirement text does not change with the phase. Expect the review and any rule changes to affect timing and assessment process, not the underlying duty to monitor alerts, advisories and directives and act on them.

How DeployOpen prepares alert and advisory evidence

DeployOpen plans and builds the alert intake, triage and records that SI.L2-3.14.3 Security alerts and advisories depends on, inside your own infrastructure. The organization still owns its response decisions, and an independent assessor is the only party that judges whether the requirement is MET.

How we scope

The written scope names which external alert sources, vendors and advisory feeds the organization must monitor for SI.L2-3.14.3.
Scope defines who receives alerts, how often reviews happen, and which systems fall inside the CUI boundary.
Engagements are fixed-scope, so deliverables and timelines are agreed in writing before any work starts.

How we build

We configure self-hosted threat intelligence tooling such as MISP or OpenCTI to ingest advisories and store them as traceable records.
Vulnerability and finding workflows such as DefectDojo are set up so alerts link to tracked remediation actions with owners.
Defined response actions are written as runbooks and tested against sample alerts so the team can show how each one was handled.

How we hand over

Handover includes the configured alert pipeline, documented response procedures, and the record templates the organization will keep.
We document how alerts are received, disseminated and acted on, so an assessor can interview staff and check the process.
Evidence is delivered in final form, with a list of which assessment objectives each artifact is meant to support.

How we support

Ongoing support, upgrades and continuous testing are available as a retainer, which keeps alert sources and tool versions current.
Reviews of alert handling can be scheduled so records keep pace with how often advisories actually arrive.
Ask your DeployOpen contact to confirm which items the retainer covers before you sign the written scope.