When a new critical vulnerability is disclosed, how quickly does it appear in the National Vulnerability Database (NVD)? And how long before it's enriched with the CVSS scores, exploit information, and remediation guidance your security team needs to make informed decisions?
Understanding the NVD's update frequency and CVE enrichment timeline is crucial for building effective vulnerability management processes. In 2025, while the NVD provides near-real-time ingestion of new CVEs, the enrichment process—adding the detailed analysis that makes CVE records truly actionable—faces significant challenges that every security professional should understand.
This article explains how the NVD update process works, the current state of CVE enrichment in 2025, and practical strategies for working within these constraints.
How the NVD Works: The CVE Lifecycle
To understand update frequency, it's helpful to understand the relationship between MITRE's CVE List and NIST's National Vulnerability Database:
Step 1: CVE Assignment (MITRE)
When a security researcher or vendor discovers a vulnerability, they request a CVE ID from a CVE Numbering Authority (CNA). MITRE maintains the authoritative CVE List, which provides:
- Unique CVE identifier (e.g., CVE-2025-12345)
- Brief description of the vulnerability
- References to advisories, reports, or patches
- Affected product information
This is the "base" CVE record—essential for tracking and communication, but lacking detailed severity scoring and analysis.
Step 2: CVE Publication
Once assigned and disclosed, the CVE is published to the CVE List. The NVD ingests these new CVEs automatically.
Step 3: NVD Enrichment (NIST)
NIST analysts enhance CVE records with additional data:
- CVSS Scores: Detailed severity ratings (Base, Temporal, and Environmental scores)
- CWE Mappings: Classification by weakness type (e.g., SQL injection, buffer overflow)
- CPE Strings: Standardized product identifiers showing affected software versions
- Additional References: Links to exploit databases, vendor advisories, and mitigation guidance
- Configuration Analysis: Details about vulnerable configurations
This enrichment transforms a basic CVE record into an actionable intelligence report that security teams can use for risk assessment and remediation planning.
NVD Update Frequency: Real-Time CVE Ingestion
The good news: CVE ingestion into the NVD is nearly real-time.
According to NIST, the NVD processes the CVE List every hour to identify new CVE publications, rejections, or modifications. New CVEs are typically available in the NVD within one hour of publication to the MITRE CVE List.
This means if a vendor discloses a vulnerability at 9:00 AM, it should appear in the NVD database (with basic information) by 10:00 AM. You can query the NVD via its web interface or API and see the new CVE record almost immediately.
API and Feed Update Schedules
The NVD provides data through multiple channels with different update frequencies:
NVD API (Recommended):
- Updated as frequently as the website
- Real-time access to the latest data
- Rate limited but suitable for automated queries
JSON Data Feeds (Legacy, being phased out):
- "Recent" and "Modified" feeds: Updated every 2 hours
- "Year" feeds (e.g., 2025 CVEs): Updated once per day
- Important: Legacy feed files will be removed on August 20, 2025—organizations still using feeds should migrate to the API
For production vulnerability management systems, the NVD API provides the most current data with the best performance characteristics.
The Enrichment Challenge: From Hours to Months
While CVE ingestion happens within an hour, enrichment with CVSS scores and detailed analysis takes considerably longer—and this is where the NVD faces significant challenges in 2025.
The Growing Backlog
As of March 2025, NIST is processing incoming CVEs at roughly the same rate as before the 2024 slowdown. However, there's a critical problem: CVE submissions increased 32% in 2024, and this growth continues into 2025. By the end of May 2025, the NVD database contained over 280,000 CVE records.
The NVD's processing capacity, while restored to previous levels, isn't sufficient to keep pace with the accelerating volume of new vulnerabilities. The enrichment backlog continues to grow despite NIST's efforts.
Enrichment Timeline: What to Expect
The time from CVE publication to full enrichment varies significantly based on several factors:
High-Priority CVEs: Critical vulnerabilities affecting widely-used software, especially those with active exploitation or significant public attention, typically receive enrichment within hours to a few days of publication.
Standard CVEs: Most vulnerabilities see enrichment within several days to a few weeks under normal circumstances, though the current backlog extends these timelines.
Lower-Priority CVEs: Less severe vulnerabilities or those affecting niche software may wait weeks to months for full enrichment, depending on backlog conditions.
Older CVEs: In 2025, NIST made a significant policy change: all CVEs published before January 1, 2018, that are awaiting enrichment are now marked as "Deferred." This means NIST does not plan to prioritize updating enrichment data for these older vulnerabilities, effectively creating a cutoff for retrospective analysis.
What Affects Enrichment Speed?
Several factors influence how quickly a CVE receives enrichment:
Complexity: Some vulnerabilities require extensive research and testing to determine accurate CVSS scores and affected configurations. A simple SQL injection is faster to analyze than a complex race condition in a kernel driver.
Information Availability: If the vendor provides detailed advisories with clear scope and CVSS scores, NIST can enrich the record more quickly. Vague disclosures require more investigation.
Resource Constraints: NIST has a finite number of analysts. When multiple major vulnerabilities are disclosed simultaneously (like a large vendor's monthly patch Tuesday), enrichment times increase.
Volume Spikes: After major security conferences, coordinated disclosure events, or large-scale security research publications, the enrichment backlog grows.
Practical Implications for Security Teams
Understanding these timelines has important implications for vulnerability management:
Don't Wait for CVSS Scores
If a vendor publishes a critical security advisory with patches available, don't wait for NIST enrichment before acting. Vendor advisories usually include their own severity assessments and remediation guidance. Treat vendor-rated "Critical" issues as critical until proven otherwise.
Multiple Data Sources
Build vulnerability intelligence from multiple sources:
- Vendor Advisories: Often the fastest and most authoritative source for new vulnerabilities
- CISA KEV Catalog: Known Exploited Vulnerabilities requiring urgent attention
- Threat Intelligence Feeds: Commercial and open-source feeds providing exploit information
- CVE List (MITRE): Base CVE information before NVD enrichment
- NVD: Comprehensive enriched data when available
Don't rely solely on NVD enrichment—it's one important piece in a broader threat intelligence picture.
Automated Scanning Frequency
Given that the NVD is continuously updated, how often should you scan for new vulnerabilities?
Daily Scanning: For production environments and internet-facing systems, daily vulnerability scans ensure you identify new CVEs affecting your assets within 24 hours of enrichment.
Weekly Review: Dedicate time each week to review new Critical and High severity CVEs affecting your technology stack, even if they haven't yet been detected in scans.
Real-Time Alerting: Configure your vulnerability management tools to alert on specific high-priority criteria:
- CVEs affecting your critical assets
- CISA KEV catalog additions
- Critical/High severity CVEs for your key vendors
Continuous Monitoring: In cloud environments or using modern vulnerability management platforms, continuous monitoring provides real-time visibility as new vulnerabilities are published and enriched.
Understand Data Lag
When reviewing vulnerability reports, check the "Last Modified" date on NVD records. A CVE published months ago with no enrichment may lack critical context. Check the vendor's advisory or security community resources for additional information.
API Best Practices
If you're building automation around the NVD API:
Rate Limiting: The NVD API has rate limits (currently 5 requests per 30 seconds without an API key, 50 requests per 30 seconds with an API key). Design your automation accordingly.
API Keys: Register for a free API key to get higher rate limits and better reliability.
Incremental Updates: Instead of downloading the entire NVD database daily, use the API's date range filters to query only recently modified CVEs (e.g., CVEs updated in the last 24 hours).
Caching: Cache NVD data appropriately. Don't query for the same CVE repeatedly within short time periods.
Error Handling: Build robust error handling for API unavailability, rate limiting, or incomplete data.
NIST's 2025 Improvements and Changes
Despite backlog challenges, NIST continues to improve the NVD:
API Migration
The transition from legacy JSON feeds to the modern NVD API provides better performance, more flexibility, and real-time data access. Organizations still using data feeds should plan migration before the August 20, 2025 deadline when legacy feeds will be permanently removed.
Deferred Status for Old CVEs
The decision to mark pre-2018 CVEs as "Deferred" helps NIST focus resources on current threats. While this means some older vulnerability records won't receive comprehensive enrichment, it allows faster processing of the vulnerabilities that matter most to modern security operations.
Process Improvements
NIST has deployed system updates and process improvements throughout 2025 to increase enrichment throughput and reduce backlog growth. While challenges remain, the trajectory is improving.
Consortium Enrichment Model
NIST has been exploring a consortium model where trusted partners could contribute enrichment data, potentially accelerating the process. While details are still emerging, this could help address the fundamental resource constraint.
Working Around Enrichment Delays
While waiting for NVD enrichment, security teams can leverage alternative data sources:
Vendor CVSS Scores
Many vendors provide their own CVSS scores in security advisories. While these should be validated, they provide useful baseline severity information immediately upon disclosure.
Vulners, VulnDB, and Commercial Databases
Commercial vulnerability databases often enrich CVE records faster than NVD, though at a subscription cost. For organizations requiring faster threat intelligence, these services provide value.
Security Community Resources
Platforms like GitHub Security Advisories, vendor-specific security communities, and security researcher blogs often provide detailed analysis of significant vulnerabilities before official enrichment.
Automated Threat Intelligence
Modern vulnerability management platforms aggregate data from NVD, vendor advisories, exploit databases, and threat intelligence feeds to provide comprehensive vulnerability context even when NVD enrichment is pending.
Monitoring the NVD
Stay informed about NVD status and changes:
- NVD News Page: https://www.nist.gov/itl/nvd/nvd-news - Official announcements
- Change Timeline: https://nvd.nist.gov/general/news/change-timeline - Detailed system changes
- NVD Status: Monitor for outages or processing delays
- CVE Statistics: NVD provides statistics on processing rates and backlog
Understanding when the NVD experiences challenges helps you adjust expectations and processes accordingly.
Conclusion
The National Vulnerability Database provides near-real-time ingestion of new CVEs—typically within one hour of publication—making it an excellent resource for tracking newly disclosed vulnerabilities. However, the enrichment process that adds critical severity scores and detailed analysis faces significant capacity challenges in 2025 due to the accelerating pace of vulnerability disclosures.
For security teams, this means:
- Don't wait for enrichment before acting on vendor-rated critical vulnerabilities
- Use multiple threat intelligence sources beyond just the NVD
- Implement daily scanning for production environments
- Monitor vendor advisories directly for your critical software
- Leverage automation via the NVD API rather than legacy feeds
- Focus on actionable intelligence over comprehensive documentation
The NVD remains an invaluable resource for vulnerability intelligence—a free, comprehensive, and authoritative source of security vulnerability data. Understanding its update cycles and current limitations allows security teams to build more effective vulnerability management processes that don't rely on a single data source.
By combining real-time NVD data with vendor advisories, threat intelligence feeds, and commercial vulnerability databases, organizations can maintain comprehensive vulnerability awareness even when official enrichment is delayed.
Ready to explore the latest vulnerabilities and understand CVSS severity ratings? Use our CVE Vulnerability Search & CVSS Calculator to query the NVD database in real-time and access the most current vulnerability intelligence available.
