Security Resilience

CVE-2021-41379

Microsoft Windows Server 2008 r2

CISA KEVActive ExploitationEUVD ExploitedRansomware-linked
Published
10 November 2021
Modified
19 August 2026
KEV Added
03 March 2022
Patch / advisory
View advisory
CVSS Score v3.1 5.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.19 97th percentile
Risk Priority 75 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2021-41379 is a medium-severity Link Following (CWE-59) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 5.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Security Account Manager (T1003.002); ranked in the top 3% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2021-41379 is an elevation of privilege vulnerability in the Windows Installer component, tracked under CWE-59 for improper link resolution before file access. It received a CVSS 3.1 score of 5.5 with a vector indicating local attack vector, low attack complexity, low privileges required, no user interaction, and high availability impact.

A local attacker with low privileges can exploit the flaw to elevate privileges and achieve high impact on system availability. The vulnerability affects Windows systems running the Installer service and can be triggered without additional user interaction once local access is obtained.

Microsoft security advisories recommend applying the patches referenced in the CVE entry to address the issue. The vulnerability is also catalogued by CISA as actively exploited in the wild, confirming real-world use beyond proof-of-concept reporting from sources such as Zero Day Initiative.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability Data

Windows Installer Elevation of Privilege Vulnerability

CWE(s)
CWE-59
KEV Date Added
03 March 2022

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003.002 Security Account Manager Credential Access
Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.
attack.mitre.org →
T1003.005 Cached Domain Credentials Credential Access
Adversaries may attempt to access cached domain credentials used to allow authentication to occur in the event a domain controller is unavailable.
attack.mitre.org →
T1011 Exfiltration Over Other Network Medium Exfiltration
Adversaries may attempt to exfiltrate data over a different network medium than the command and control channel.
attack.mitre.org →
T1016 System Network Configuration Discovery Discovery
Adversaries may look for details about the network configuration and settings, such as IP and/or MAC addresses, of systems they access or through information discovery of remote systems.
attack.mitre.org →
T1020 Automated Exfiltration Exfiltration
Adversaries may exfiltrate data, such as sensitive documents, through the use of automated processing after being gathered during Collection.
attack.mitre.org →
T1021.003 Distributed Component Object Model Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2022-21919Same product: Microsoft Windows 10 1507both on KEV
CVE-2020-0787Same product: Microsoft Windows 10 1507both on KEV
CVE-2020-0683Same product: Microsoft Windows 10 1507both on KEV
CVE-2023-36874Same product: Microsoft Windows 10 1507both on KEV
CVE-2022-21999Same product: Microsoft Windows 10 1507both on KEV
CVE-2019-1315Same product: Microsoft Windows 10 1607both on KEV
CVE-2019-1130Same product: Microsoft Windows 10 1507both on KEV
CVE-2025-21391Same product: Microsoft Windows 10 1507both on KEV
CVE-2019-1069Same product: Microsoft Windows 10 1507both on KEV
CVE-2019-1064Same product: Microsoft Windows 10 1607both on KEV

Affected Assets

microsoft
windows 10 1507
≤ 10.0.10240.19119
microsoft
windows 10 1607
≤ 10.0.14393.4770
microsoft
windows 10 1809
≤ 10.0.17763.2300
microsoft
windows 10 1909
≤ 10.0.18363.1916
microsoft
windows 10 2004
≤ 10.0.19041.1348
microsoft
windows 10 20h2
≤ 10.0.19042.1348
microsoft
windows 10 21h1
≤ 10.0.19043.1348
microsoft
windows 11 21h2
≤ 10.0.22000.318
microsoft
windows 7
all versions
microsoft
windows 8.1
all versions
+8 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 partial match
blocks

Secure SDLC practices directly require code to validate paths and avoid unsafe link following.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References