CVE-2018-25366 in CuteFTP
Summary
by MITRE • 05/26/2026
CuteFTP 5.0 XP contains a buffer overflow vulnerability that allows local attackers to execute arbitrary code by injecting malicious payload into the Site Manager label field. Attackers can craft a payload exceeding 520 bytes that overwrites the return address and executes shellcode when a shortcut is created and launched.
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Analysis
by VulDB Data Team • 05/26/2026
The vulnerability in CuteFTP 5.0 XP represents a critical buffer overflow flaw that exploits improper input validation within the Site Manager label field functionality. This weakness enables local attackers to escalate privileges and execute arbitrary code through carefully crafted malicious payloads. The vulnerability stems from insufficient bounds checking when processing user input in the label field, creating an exploitable condition that can be leveraged for system compromise. The specific overflow occurs when a payload exceeding 520 bytes is injected into the Site Manager label field, which then gets processed during shortcut creation and execution phases.
This buffer overflow vulnerability falls under the CWE-121 category of stack-based buffer overflow, where insufficient boundary checking allows memory corruption to occur. The attack vector specifically targets the application's handling of user-defined labels within the Site Manager component, making it particularly dangerous as it requires minimal user interaction to exploit. When a malicious payload is injected and processed, the overflow overwrites the return address on the stack, redirecting execution flow to the attacker-controlled shellcode. The vulnerability's exploitation requires local access to the system but can result in complete system compromise, as the application runs with elevated privileges typically associated with user sessions.
The operational impact of this vulnerability extends beyond simple code execution to encompass potential privilege escalation and persistent access mechanisms. Local attackers who successfully exploit this flaw can gain unauthorized access to system resources, potentially leading to data theft, system modification, or further network infiltration. The vulnerability affects the application's integrity and confidentiality, as attackers can manipulate the application's behavior to execute malicious operations. The exploitation process does not require network connectivity, making it particularly concerning for environments where local privilege escalation is a significant security risk.
Mitigation strategies for this vulnerability should focus on immediate patching and application hardening measures. Organizations should prioritize updating to patched versions of CuteFTP that address the buffer overflow condition through proper input validation and bounds checking. Implementing application whitelisting controls can prevent unauthorized code execution by restricting the application's ability to create or execute malicious shortcuts. Network segmentation and access controls should limit local system access to reduce the attack surface. Additionally, security monitoring should be enhanced to detect unusual shortcut creation patterns or abnormal application behavior that may indicate exploitation attempts. The vulnerability demonstrates the importance of input validation and memory safety practices in preventing buffer overflow exploits, aligning with defensive techniques recommended in the MITRE ATT&CK framework for privilege escalation and execution tactics.