Cyber Resilience

CVE-2021-47886

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 0.0013 2.8th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2021-47886 is a high-severity Unquoted Search Path or Element (CWE-428) vulnerability in Pingzapper (inferred from references). 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 2.8th 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 RA-5 (Vulnerability Monitoring and Scanning).

Deeper analysis

CVE-2021-47886 is an unquoted service path vulnerability in Pingzapper version 2.3.1, affecting the PingzapperSvc service. The issue arises from the unquoted service path 'C:\Program Files (x86)\Pingzapper\PZService.exe', which corresponds to CWE-428. This flaw allows local attackers to potentially execute arbitrary code by exploiting the vulnerability in the Windows service configuration.

Local attackers with low privileges (PR:L) can exploit this vulnerability with low attack complexity (AC:L), local access (AV:L), and no user interaction (UI:N) required, as reflected in its CVSS v3.1 base score of 7.8 (High). Exploitation involves placing malicious executables in directories traversed before the legitimate service binary, enabling privilege escalation upon service restart or execution.

Advisories and resources, including the Vulncheck advisory at https://www.vulncheck.com/advisories/pingzapper-pingzappersvc-unquoted-service-path, provide further details on the vulnerability. A proof-of-concept exploit is publicly available at https://www.exploit-db.com/exploits/49626. Vendor information is accessible via https://pingzapper.com and https://pingzapper.com/download.

EU & UK References

Vulnerability details

Pingzapper 2.3.1 contains an unquoted service path vulnerability in the PingzapperSvc service that allows local attackers to potentially execute arbitrary code. Attackers can exploit the unquoted path in 'C:\Program Files (x86)\Pingzapper\PZService.exe' to inject malicious executables and escalate privileges.

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.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Unquoted service path directly enables path interception by unquoted path (T1574.009) for local privilege escalation (T1068) via malicious binary placement before service executable.

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

CVEs Like This One

CVE-2022-50914Shared CWE-428
CVE-2020-36982Shared CWE-428
CVE-2020-36987Shared CWE-428
CVE-2021-47825Shared CWE-428
CVE-2020-37059Shared CWE-428
CVE-2020-36953Shared CWE-428
CVE-2022-50935Shared CWE-428
CVE-2021-47864Shared CWE-428
CVE-2020-37060Shared CWE-428
CVE-2019-25308Shared CWE-428

Affected Assets

Pingzapper
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Enforces and maintains secure configuration settings for system services, including proper quoting of executable paths to directly prevent exploitation of unquoted service path vulnerabilities like CVE-2021-47886.

prevent

Requires timely identification, reporting, and remediation of system flaws, directly addressing the unquoted service path vulnerability in PingzapperSvc exploited by CVE-2021-47886.

detect

Mandates vulnerability scanning that identifies unquoted service path issues like CVE-2021-47886 in Windows services such as PingzapperSvc.

References