CVE-2017-20226: Mapscrn Buffer Overflow Vulnerability

CVE-2017-20226 Overview

Mapscrn 2.0.3 contains a stack-based buffer overflow vulnerability (CWE-787: Out-of-Bounds Write) that allows local attackers to execute arbitrary code by supplying an oversized input buffer. Attackers can craft a malicious buffer with junk data, return address, NOP instructions, and shellcode to overflow the stack and achieve code execution or denial of service.

Critical Impact

Local attackers can exploit this stack-based buffer overflow to gain arbitrary code execution or cause denial of service on affected systems running Mapscrn 2.0.3.

Affected Products

• Mapscrn version 2.0.3

Discovery Timeline

• 2026-03-28 - CVE CVE-2017-20226 published to NVD
• 2026-03-30 - Last updated in NVD database

Technical Details for CVE-2017-20226

Vulnerability Analysis

This vulnerability is classified as a stack-based buffer overflow (CWE-787: Out-of-Bounds Write), which occurs when the application writes data beyond the boundaries of allocated stack memory. In Mapscrn 2.0.3, the application fails to properly validate the size of user-supplied input before copying it into a fixed-size stack buffer.

The local attack vector means an attacker requires local access to the system to exploit this vulnerability. The attack complexity is low, requiring no special privileges or user interaction to execute. Successful exploitation can result in complete compromise of confidentiality, integrity, and availability of the affected system.

Root Cause

The root cause of this vulnerability is insufficient bounds checking on user-supplied input before it is copied into a stack-allocated buffer. When an input buffer larger than the allocated stack space is provided, the excess data overwrites adjacent memory regions on the stack, including the saved return address. This classic buffer overflow condition allows attackers to redirect program execution flow.

Attack Vector

The attack is executed locally by supplying a specially crafted oversized input buffer to the vulnerable Mapscrn application. The exploitation technique follows standard stack-based buffer overflow methodology:

1. The attacker constructs a payload containing junk data to fill the buffer up to the return address location
2. The payload includes a crafted return address pointing to attacker-controlled memory
3. NOP sled instructions are added to increase the reliability of exploitation
4. Shellcode is appended to execute arbitrary commands when control is transferred

The vulnerability manifests when the oversized buffer is processed, causing the stack to be overwritten and enabling arbitrary code execution. For detailed technical information and proof-of-concept details, refer to the Exploit-DB #42144 entry and the VulnCheck Advisory on Buffer Overflow.

Detection Methods for CVE-2017-20226

Indicators of Compromise

• Unexpected crashes or abnormal termination of the Mapscrn process
• Stack smashing detection alerts from system security mechanisms
• Unusual process behavior or spawned child processes from Mapscrn
• Memory access violations or segmentation faults in system logs

Detection Strategies

• Monitor for abnormally large input being passed to Mapscrn processes
• Deploy host-based intrusion detection systems (HIDS) to detect buffer overflow exploitation attempts
• Enable Address Space Layout Randomization (ASLR) and stack canary protections to detect overflow attempts
• Implement application-level logging to capture unusual input patterns

Monitoring Recommendations

• Configure system audit logging to capture process execution anomalies
• Monitor for unexpected privilege escalation following Mapscrn execution
• Set up alerts for repeated crashes or restarts of the Mapscrn application
• Review system logs for signs of exploitation attempts or shellcode execution

How to Mitigate CVE-2017-20226

Immediate Actions Required

• Restrict local access to systems running vulnerable Mapscrn 2.0.3 installations
• Remove or disable Mapscrn 2.0.3 if it is not essential to system operations
• Apply operating system-level protections such as ASLR, DEP/NX, and stack canaries
• Monitor affected systems for signs of exploitation attempts

Patch Information

No vendor patch information is currently available in the CVE data. Organizations should monitor the VulnCheck Advisory for updated remediation guidance. Consider upgrading to a newer version of Mapscrn if available, or replacing the software with an alternative solution.

Workarounds

• Restrict local user access to systems running Mapscrn 2.0.3 to trusted users only
• Enable compiler-level security features such as stack protectors and ASLR on the host system
• Consider running Mapscrn in a sandboxed or containerized environment to limit exploitation impact
• Implement input validation at the system level to reject oversized buffers before they reach the application