Cyber Resilience

CVE-2021-47882

HighPublic PoC

Published: 21 January 2026

Published
21 January 2026
Modified
15 April 2026
KEV Added
Patch
CVSS Score v4 8.5 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0014 3.5th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2021-47882 is a high-severity Unquoted Search Path or Element (CWE-428) vulnerability. Its CVSS base score is 8.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception by Unquoted Path (T1574.009); ranked at the 3.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 CM-6 (Configuration Settings) and SI-2 (Flaw Remediation).

Deeper analysis

CVE-2021-47882 is an unquoted service path vulnerability in FreeLAN version 2.2, specifically within its Windows service configuration. This flaw, classified under CWE-428, occurs because the service binary path lacks proper quoting, enabling path hijacking. It affects Windows installations of FreeLAN 2.2, a peer-to-peer VPN software, and was published on 2026-01-21 with a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

Local attackers with low-privilege access can exploit this vulnerability by placing a malicious executable in a directory that aligns with the unquoted service path resolution order. When the FreeLAN service starts, the injected executable launches with elevated LocalSystem privileges, allowing arbitrary code execution and potential full system compromise, including high impacts on confidentiality, integrity, and availability.

Advisories and related resources include the FreeLAN GitHub repository at https://github.com/freelan-developers/freelan, an Exploit-DB entry at https://www.exploit-db.com/exploits/49630, and a Vulncheck advisory at https://www.vulncheck.com/advisories/freelan-freelan-service-unquoted-service-path, which provide further details on the issue and potential exploitation.

EU & UK References

Vulnerability details

FreeLAN 2.2 contains an unquoted service path vulnerability in its Windows service configuration that allows local attackers to execute arbitrary code. Attackers can exploit the unquoted binary path to inject malicious executables that will be launched with elevated LocalSystem privileges…

more

during service startup.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1574.009 Path Interception by Unquoted Path Stealth
Adversaries may execute their own malicious payloads by hijacking vulnerable file path references.
Why these techniques?

Direct mapping of unquoted service path (CWE-428) to path interception by unquoted path for privilege escalation via malicious executable placement in service binary resolution.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2020-36928Shared CWE-428
CVE-2023-54336Shared CWE-428
CVE-2020-37048Shared CWE-428
CVE-2019-25306Shared CWE-428
CVE-2020-36979Shared CWE-428
CVE-2020-36929Shared CWE-428
CVE-2020-37017Shared CWE-428
CVE-2021-47859Shared CWE-428
CVE-2019-25309Shared CWE-428
CVE-2021-47790Shared CWE-428

Affected Assets

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Establishes and maintains secure configuration settings for Windows services, ensuring binary paths are properly quoted to directly prevent unquoted service path hijacking.

prevent

Requires identification, reporting, and timely remediation of flaws like unquoted service paths via patches or configuration fixes.

prevent

Enforces least privilege for service accounts, limiting the scope of privilege escalation even if a malicious executable is launched via path hijacking.

References