China’s CNVD CNNVD Databases Create Vulnerability Disclosure Gaps

China maintains two national vulnerability databases, CNVD and CNNVD, that reveal security flaws months before Western databases. These systems create informational asymmetry exploited by threat actors. Enterprises relying solely on CVE/NVD remain blind to “Red Vulns” during critical exposure windows.

Bitsight analysis compared publication timestamps across ecosystems. CNNVD largely mirrors MITRE CVE entries. CNVD publishes unique vulnerabilities with independent timelines and deliberate disclosure delays.

Strategic latency turns vulnerability intelligence into national security assets rather than public goods. Attackers weaponize flaws like OneDrive DLL hijacking before global patches deploy.

High-severity vulnerabilities appear in CNVD while absent from NVD. Disclosure delays exceed weeks for sensitive entries. Global defenders lack IOCs during active exploitation phases.

CNVD maintains a shadow inventory unmapped to CVE numbers. Severity ratings differ across borders. Enterprise security teams must monitor both databases for complete coverage.

Database Comparison Matrix

Database	Operator	CVE Alignment	Disclosure Speed	Unique Entries
CNVD	CNCERT/CC	Partial	Delayed (weeks+)	High
CNNVD	NSFOCUS	Strong	Mirrors CVE	Low
NVD	NIST	Global standard	24-72 hours	None
CVE	MITRE	Master list	Vendor submission	Master IDs

CNVD growth matches global standards but prioritizes national security over rapid disclosure.

Disclosure Delay Patterns

Strategic latency arcs:

• High/Critical CVEs held back >30 days
• Zero-day indicators published post-exploitation
• CNVD “event-based” entries precede CVE
• OneDrive DLL hijacking cataloged pre-CVE equivalent

Key example:

CNVD-2024-xxxxx: OneDrive DLL Hijacking (High)
Published months before comparable CVE
Enabled targeted attacks during patch gap

Bitsight identified systematic patterns where submission-to-publication exceeds one week.

Vulnerability Timeline Examples

CVE/ID	Name	CNVD Date	NVD Date	Delay	Severity
CVE-2024-33698	Generic	Early 2024	Mid 2024	4 months	High
CNVD-2024-xxxxx	OneDrive DLL	Q1 2024	No CVE	N/A	High
CNVD-202-35587	Bitcoin DoS	2022	No CVE	N/A	Medium
CVE-2021-40444	MSHTML RCE	Reference	Reference	Baseline	Critical

CNVD entries often lack direct CVE mapping, creating shadow inventory.

Attack Implications

Weaponization window:

• Chinese actors exploit during disclosure blackout
• Western EDR/SIEM blind to CNVD-tracked IOCs
• Patch cycles lag vulnerability awareness
• Persistence established pre-detection

OneDrive DLL hijacking case:
1. CNVD publishes flaw details
2. State actors develop exploit
3. Western vendors unaware
4. Months pass before CVE/NVD sync
5. Targeted intrusions complete


Severity Distribution Differences

Risk rating divergence:
CVE: CVSS v3.1 standardized
CNVD: National priority scoring
Result: Medium CNVD = Critical CVE


Organizations misprioritize when using single-source intelligence.

Intelligence Requirements

Multi-source monitoring:
NVD + CNVD + CNNVD + CVE daily sync
Chinese-language vuln feeds
Event-based CNVD entries
Delay arc tracking


Enterprise actions:

• Automate CNVD/CNNVD API polling
• Cross-reference CVE mappings
• Prioritize CNVD High/Critical entries
• Track unmapped shadow inventory

Geopolitical Risk Factors

National security divergence:

• CNVD serves Chinese defense priorities
• Disclosure serves strategic objectives
• Zero-days weaponized during blackout
• Global patch cycles irrelevant

Supply chain impact:
Western software dominates CNVD
Microsoft, Adobe, Oracle heavily tracked
Chinese vendors receive preferential treatment


Detection Engineering Challenges

Signature gaps:
CNVD IOCs absent from Western platforms
YARA/Sigma rules lag publication
SIEM content misses shadow inventory


Threat hunting:
Query CNVD by vendor/product
Monitor delay arcs >14 days
Track unmapped High/Critical entries
Validate against NVD/CVE sync


Strategic Recommendations

Immediate:
Subscribe CNVD English RSS
API integration vulnerability scanners
Daily delta scans both databases
Prioritize CNVD-only High entries


Long-term:
Multi-lingual threat intelligence
Automated CVE-CNVD correlation
Delay arc alerting
Shadow inventory tracking


FAQ