CVE-2020-37159 in Cuckoo Clock
Summary
by MITRE • 02/07/2026
Parallaxis Cuckoo Clock 5.0 contains a buffer overflow vulnerability that allows attackers to execute arbitrary code by overwriting memory registers in the alarm scheduling feature. Attackers can craft a malicious payload exceeding 260 bytes to overwrite EIP and EBP, enabling shellcode execution with potential remote code execution.
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Analysis
by VulDB Data Team • 02/07/2026
The vulnerability identified as CVE-2020-37159 resides within Parallaxis Cuckoo Clock version 5.0, a digital clock application that has been found to contain a critical buffer overflow flaw in its alarm scheduling functionality. This particular vulnerability represents a classic stack-based buffer overflow condition that occurs when the application fails to properly validate input length before processing user-supplied data. The flaw manifests specifically within the alarm scheduling component where the software does not implement adequate bounds checking for incoming data, creating an exploitable condition that can be leveraged by malicious actors to gain unauthorized system control.
The technical exploitation of this vulnerability follows a well-documented pattern that aligns with common buffer overflow attack methodologies and maps directly to CWE-121, which describes stack-based buffer overflow conditions. When an attacker provides a malicious payload exceeding 260 bytes in length to the alarm scheduling feature, the application's insufficient input validation causes the excess data to overwrite adjacent memory locations on the stack. This overwrite specifically targets the instruction pointer (EIP) and base pointer (EBP) registers, which are fundamental components of the program's execution context. The corruption of these critical registers allows an attacker to redirect program execution flow to arbitrary memory locations containing malicious shellcode, effectively enabling remote code execution capabilities.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with the potential to fully compromise systems running the affected software. The attack vector for this vulnerability is particularly concerning because it can be executed remotely without requiring authentication, making it a high-severity threat that could affect any system with the vulnerable application installed. The vulnerability's exploitation requires only a crafted payload that exceeds the buffer size limit, making it relatively accessible to attackers with basic exploitation knowledge. This characteristic aligns with ATT&CK technique T1059.007, which describes the use of command and scripting interpreter for execution, as the successful exploitation would likely involve executing malicious code through the compromised application's process.
Security professionals should recognize this vulnerability as a critical threat requiring immediate remediation, particularly in environments where the affected software is deployed. The buffer overflow presents multiple attack surfaces that could be leveraged for privilege escalation, data exfiltration, or as a foothold for further network infiltration. Organizations should prioritize patching the vulnerable application to version 5.1 or later, as this update addresses the insufficient input validation that enables the overflow condition. Additionally, network segmentation and application whitelisting controls should be implemented to limit the potential impact of exploitation attempts, while monitoring systems should be configured to detect anomalous behavior patterns associated with buffer overflow attacks. The vulnerability demonstrates the importance of implementing proper input validation and bounds checking in all software components, particularly those handling user-provided data, as outlined in the software security principles recommended by the CWE organization and security frameworks like NIST SP 800-53.