Cyber Resilience

CVE-2021-47790

HighPublic PoC

Published: 16 January 2026

Published
16 January 2026
Modified
30 January 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 0.0021 10.7th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2021-47790 is a high-severity Unquoted Search Path or Element (CWE-428) vulnerability in Pysoft Active Webcam. 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 10.7th 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-2021-47790 is an unquoted service path vulnerability in Active WebCam 11.5. This flaw stems from a misconfigured service path (CWE-428), enabling local attackers to execute arbitrary code with elevated system privileges by placing malicious executables in specific directory locations along the search path.

The vulnerability can be exploited by local attackers who already possess low privileges (PR:L), requiring low attack complexity (AC:L) and no user interaction (UI:N). Successful exploitation grants administrative access, with high impacts on confidentiality, integrity, and availability, as reflected in its CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

Advisories from VulnCheck (https://www.vulncheck.com/advisories/active-webcam-unquoted-service-path) and an exploit published on Exploit-DB (https://www.exploit-db.com/exploits/50273) document the issue, while the vendor site (https://www.pysoft.com/) and download pages like TechSpot (https://www.techspot.com/downloads/175-active-webcam.html) provide context on the affected software; no specific patches or mitigations are detailed in the referenced materials.

A public proof-of-concept exploit is available on Exploit-DB, indicating potential for real-world local privilege escalation on unpatched systems.

EU & UK References

Vulnerability details

Active WebCam 11.5 contains an unquoted service path vulnerability that allows local attackers to execute arbitrary code with elevated system privileges. Attackers can exploit the misconfigured service path by placing malicious executables in specific directory locations to gain administrative access.

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?

Unquoted service path (CWE-428) directly enables path interception by unquoted path for local privilege escalation via malicious executable placement.

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-2022-50929Shared CWE-428

Affected Assets

pysoft
active webcam
11.5

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Enforces secure configuration settings for system services, directly preventing unquoted service path vulnerabilities by requiring properly quoted executable paths.

prevent

Requires timely identification, reporting, and remediation of flaws like the unquoted service path in Active WebCam 11.5 to eliminate the vulnerability.

prevent

Applies least privilege to services, reducing the impact of privilege escalation even if an attacker exploits the unquoted service path.

References