CVE-2020-37037
Published: 01 February 2026
Summary
CVE-2020-37037 is a high-severity Unquoted Search Path or Element (CWE-428) vulnerability in Avast SecureLine (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 4.5th 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-2020-37037 is an unquoted service path vulnerability (CWE-428) affecting Avast SecureLine version 5.5.522.0. The flaw exists in the service configuration, where the unquoted path allows local users to potentially execute arbitrary code with elevated system privileges. This issue has 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), indicating high severity due to its potential for significant impact on confidentiality, integrity, and availability.
Local attackers with low privileges (PR:L) can exploit this vulnerability by placing a malicious executable in a directory that precedes the legitimate service binary in the system's search path. Upon service startup, the injected code executes with LocalSystem account permissions, enabling full system compromise, including unauthorized access to sensitive data, modification of system files, and disruption of services.
Advisories and related resources, including those from Vulncheck (https://www.vulncheck.com/advisories/avast-secureline-secureline-unquoted-service-path) and Avast (https://www.avast.com/), provide details on the issue. A proof-of-concept exploit is publicly available at Exploit-DB (https://www.exploit-db.com/exploits/48249), demonstrating practical exploitation.
In real-world context, the availability of a public exploit highlights the risk of active exploitation against unpatched systems running the affected Avast SecureLine version.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2020-30973
Vulnerability details
Avast SecureLine 5.5.522.0 contains an unquoted service path vulnerability that allows local users to potentially execute code with elevated system privileges. Attackers can exploit the unquoted path in the service configuration to inject malicious code that would execute with LocalSystem…
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account permissions during service startup.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Unquoted service path (CWE-428) directly enables path interception by unquoted path for local privilege escalation to SYSTEM via malicious binary placement.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Mandates secure configuration settings for services, including properly quoted executable paths, to directly prevent path hijacking exploits like CVE-2020-37037.
Requires timely identification, assessment, and remediation of flaws such as the unquoted service path in Avast SecureLine, preventing exploitation through patching.
Enforces least privilege for service accounts, limiting the impact of privilege escalation even if path hijacking occurs during service startup.