CVE-2026-67673 in Firmware
Summary
by MITRE • 08/04/2026
A stack-based buffer overflow vulnerability exists in the cmd_edl function of OreSat Firmware v1.0. The vulnerability is triggered when processing the edl fw_flash command, where the <filename> argument is copied to a 64-byte stack buffer via memcpy without proper length validation. An attacker with physical access to the UART3 serial interface can exploit this vulnerability by sending a maliciously crafted command with an oversized filename parameter,
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Analysis
by VulDB Data Team • 08/04/2026
The stack-based buffer overflow vulnerability in OreSat Firmware v1.0 represents a critical security flaw that undermines the integrity of the device's operational environment. This vulnerability specifically affects the cmd_edl function which processes firmware flash commands through the UART3 serial interface. The flaw stems from inadequate input validation mechanisms that fail to enforce bounds checking on user-supplied data, creating an exploitable condition where attacker-controlled data can overwrite adjacent memory locations on the stack.
The technical implementation of this vulnerability involves a dangerous use of memcpy function without proper size validation. When the edl fw_flash command is processed, the system copies the <filename> argument directly into a 64-byte stack buffer without verifying that the input length exceeds the allocated space. This classic buffer overflow scenario allows an attacker to overwrite the return address and potentially other stack variables, providing a pathway for arbitrary code execution. The vulnerability's classification aligns with CWE-121 Stack-based Buffer Overflow, which specifically addresses buffer overflows occurring in stack memory regions.
The operational impact of this vulnerability is particularly severe given that it can be exploited through physical access to the UART3 serial interface. This attack vector reduces the complexity of exploitation compared to network-based attacks, as the attacker only needs to establish a physical connection to the device's serial port rather than overcoming network security measures. Once exploited, the buffer overflow could enable an attacker to execute arbitrary code with the privileges of the firmware process, potentially leading to complete system compromise and unauthorized firmware modifications.
The security implications extend beyond simple code execution through alignment with several ATT&CK techniques including T1059 Command and Scripting Interpreter and T1210 Exploitation of Remote Services. The vulnerability creates opportunities for persistent access and privilege escalation attacks, particularly concerning the device's firmware update mechanisms which are critical to maintaining system integrity. Organizations should implement input validation controls and bounds checking as fundamental defensive measures against such memory corruption vulnerabilities.
Mitigation strategies should focus on immediate code-level fixes including proper length validation before buffer operations, implementing stack canaries for additional protection, and employing modern compiler security features such as stack smashing protection. The firmware should be updated with bounds checking mechanisms that verify the filename argument length against the allocated 64-byte buffer size before any memory copying operations occur. Additionally, access controls should be implemented to restrict physical access to UART3 interfaces where possible, reducing the attack surface for this particular vulnerability.
The broader security landscape recognizes such vulnerabilities as critical threats in embedded systems environments where physical access often correlates with elevated privilege levels. This vulnerability exemplifies why robust input validation and secure coding practices are essential in firmware development, particularly for space-based systems like OreSat where reliability and security are paramount considerations. The incident underscores the necessity of comprehensive security testing including fuzzing and static analysis to identify similar buffer overflow conditions before deployment in operational environments.
This vulnerability serves as a reminder of the importance of adhering to secure coding guidelines such as those recommended by the CERT Secure Coding Standards, which specifically address preventing buffer overflows through proper input validation and memory management practices. The exploitation potential of such flaws demonstrates why continuous security assessments and code reviews are essential components of embedded system development lifecycle processes, particularly in mission-critical applications where device compromise could lead to significant operational disruptions or safety concerns.