CVE-2021-36942

ENISA EUVD: EUVD-2021-23518 ↗
Exploited in the Wild ✓ Confirmed 0-Day
Triaged: March 20, 2026 4 articles Published: 2021-08-12
VulnLookup ↗ NVD ↗ EUVD ↗ MITRE ↗ CISA KEV ↗

EPSS Score

Source: FIRST.org · 2026-05-23
93.73%
probability
This CVE has a 93.73% probability of being exploited in the next 30 days.
0% Top 99.9th percentile of all CVEs 100%

CVSS v3.1

Source: VulnerabilityLookup (CIRCL)
7.5
HIGH
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Temporal
Exploit Code Maturity
Functional
Remediation Level
Official Fix
Report Confidence
Confirmed
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:F/RL:O/RC:C

CVSS v2 (legacy)

5.0
MEDIUM
Access Vector
Network
Access Complexity
Low
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
AV:N/AC:L/Au:N/C:N/I:P/A:N

Description

NVD
Windows LSA Spoofing Vulnerability

Affected Products

Microsoft
Windows Server 2019
10.0.0
Microsoft
Windows Server 2019 (Server Core installation)
10.0.0
Microsoft
Windows Server version 2004
10.0.0
Microsoft
Windows Server version 20H2
10.0.0
Microsoft
Windows Server 2016
10.0.0

Signal Intelligence

Confidenceⓘ
85%
EPSS 93.73%
CVSS v3.1 7.5
Mentions 4
Last Seen May 08, 2025

CNA Information

CNA Assigner
microsoft
CNA Title
Windows LSA Spoofing Vulnerability

Analyst Note

CVE-2021-36942 is explicitly named in the August 2021 Microsoft Patch Tuesday article as a critical Windows LSA vulnerability included among three 0-day patches released that month. The explicit identification as a 0-day in an authoritative Qualys Patch Tuesday report, combined with simultaneous patch and vulnerability disclosure timing (August 2021), meets the confirmation criteria for zero-day classification.

Threat Actors 6

APT27
apt_group Information theft and espionage 🇨🇳 CN
Cron
apt_group 🇷🇺 RU
Hacking Team
apt_group 🇮🇹 IT
TA505
apt_group Financial gain 🇷🇺 RU
Shadow Network
apt_group Information theft and espionage 🇨🇳 CN
Operation Shadow Force
apt_group 🇨🇳 CN

Triage Info

Decided atMar 20, 2026
Published DateAug 12, 2021