CVE-2021-20021
ENISA EUVD: EUVD-2021-7484 ↗
Exploited in the Wild
✓ Confirmed 0-Day
Triaged: March 20, 2026
2 articles
EPSS Score
Source: FIRST.org · 2026-05-24
91.22%
probability
This CVE has a 91.22% probability
of being exploited in the next 30 days.
0%
Top 99.7th percentile of all CVEs
100%
CVSS v3.1
Source: NVD9.8
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected Products
SonicWall warns customers to patch 3 zero-days exploited in the wild
BleepingComputer
Apr 20, 2021
Signal Intelligence
Confidence
85%
EPSS
91.22%
CVSS v3.1
9.8
Mentions
2
Last Seen
Apr 20, 2021
CNA Information
Analyst Note
CVE-2021-20021 is explicitly named as a zero-day vulnerability actively exploited in the wild by SonicWall in 2021. Multiple authoritative sources (TheHackerNews, BleepingComputer) confirm active exploitation and vendor patching concurrent with disclosure, meeting zero-day criteria.
Triage Info
Decided atMar 20, 2026