CVE-2026-79298 in SysReturn
Summary
by MITRE • 09/16/2026
An issue in Howyar Technologies Inc SysReturn Versions prior to 11.3.034 and fixed in v.11.3.0.34 allows a local attcker to execute arbitrary code via the BOOTia32.efi and a crafted cloak32.dat file on the ESP.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 09/16/2026
The vulnerability identified in Howyar Technologies Inc SysReturn versions prior to 11.3.034 represents a critical security flaw within the system's boot process, specifically affecting the interaction between the EFI application BOOTia32.efi and its configuration file cloak32.dat located on the EFI System Partition. This issue enables a local attacker with physical access or the ability to modify files on the ESP to execute arbitrary code during the early stages of system initialization. The core technical flaw stems from insufficient validation or sanitization mechanisms within the BOOTia32.efi application when parsing the cloak32.dat file. By crafting a maliciously formatted cloak32.dat file, an attacker can exploit buffer overflow conditions or logic errors in how the EFI binary processes input data, leading to arbitrary code execution with the privileges of the boot environment, which typically includes high-level system access before full operating system security controls are initialized.
From a technical perspective, this vulnerability aligns with CWE-120 Buffer Copy without Checking Size of Input and potentially CWE-78 Improper Neutralization of Special Elements used in an OS Command if the execution path involves shell commands or similar mechanisms. The attack vector is classified as Local because it requires physical access to the machine or prior compromise of the EFI System Partition, which serves as a trusted storage area for boot-related files. This places the vulnerability within the context of ATT&CK technique T1531 Accessing Cloud Storage Objects if the ESP is synchronized via cloud services, but more accurately maps to T1059 Command and Scripting Interpreter or T1204 User Execution depending on how the payload is delivered. However, given it occurs during boot, it also relates to persistence mechanisms where an attacker can establish a foothold that survives operating system reinstalls if not properly addressed in firmware updates.
The operational impact of this vulnerability is severe due to its location within the pre-boot environment. An attacker who successfully exploits this flaw gains control over the system before the main operating system loads, allowing them to bypass traditional endpoint security solutions such as antivirus software and host-based firewalls that are only active after OS initialization. This capability facilitates privilege escalation from a low-privilege local user or physical intruder to full administrative rights on the target machine. Furthermore, it allows for the installation of rootkits or bootkits that can persist across reboots and operating system reinstalls, making detection and remediation significantly more difficult compared to standard application-layer vulnerabilities. The attacker could potentially exfiltrate sensitive data stored in memory during early boot stages or modify critical system files before integrity checks are performed by the OS.
Mitigation strategies primarily involve updating the SysReturn software to version 11.3.034 or later, where this issue has been resolved through improved input validation and secure coding practices within the BOOTia32.efi component. Organizations should also implement strict access controls on the EFI System Partition to prevent unauthorized modification of boot files by local users or services. Physical security measures are essential since the attack vector requires physical presence or prior file system compromise. Additionally, enabling Secure Boot can help mitigate some risks by ensuring that only signed and trusted binaries are executed during the boot process, although this depends on the specific implementation details of how SYSReturn interacts with UEFI secure boot policies. Regular auditing of ESP contents and monitoring for unauthorized changes to critical boot files should be part of a comprehensive defense-in-depth strategy against pre-boot attacks.