CVE-2020-37031: Simple Startup Manager Buffer Overflow

CVE-2020-37031 Overview

CVE-2020-37031 is a local buffer overflow vulnerability in Ashkon Simple Startup Manager 1.17. Attackers can exploit improper bounds checking in the File input parameter to corrupt memory and execute arbitrary code. A crafted payload of 268 bytes overwrites adjacent memory regions and bypasses Data Execution Prevention (DEP) to launch calc.exe as a proof of concept. The flaw is categorized under CWE-787: Out-of-bounds Write. Successful exploitation grants attackers the ability to run code with the privileges of the user running the application.

Critical Impact

Local attackers can achieve arbitrary code execution on Windows systems running Simple Startup Manager 1.17 by submitting an oversized File parameter, bypassing DEP protections.

Affected Products

• Ashkon Simple Startup Manager 1.17
• Windows installations running the vulnerable version
• Systems where DEP is the sole memory protection mechanism

Discovery Timeline

• 2026-01-30 - CVE-2020-37031 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2020-37031

Vulnerability Analysis

The vulnerability resides in how Simple Startup Manager 1.17 processes the File input parameter. The application copies user-supplied input into a fixed-size stack buffer without validating the input length. Supplying 268 bytes overflows the buffer and overwrites the saved return address on the stack. Attackers gain control of the instruction pointer and redirect execution to attacker-chosen memory.

The exploit chain uses Return-Oriented Programming (ROP) gadgets to bypass DEP. ROP gadgets call Windows API functions such as VirtualProtect or WriteProcessMemory to mark shellcode regions as executable. Public proof-of-concept code demonstrates execution of calc.exe as a benign payload. Real-world exploitation would substitute arbitrary shellcode for persistence, credential theft, or lateral movement.

The vulnerability is classified under CWE-787: Out-of-bounds Write. Technical exploit details are documented in Exploit-DB #48678 and the VulnCheck Advisory on Buffer Overflow.

Root Cause

The root cause is the absence of bounds checking when copying the File parameter into a stack-allocated buffer. The application uses unsafe string handling routines that do not enforce a maximum length. Input exceeding the buffer size writes past its boundary and overwrites the saved return address and adjacent stack frames.

Attack Vector

Exploitation requires local access. An attacker must run the application and supply a malicious File parameter, or trick a user into opening a crafted input file. The attack does not require authentication or elevated privileges beyond those of the application user. Refer to Exploit-DB #48678 for the published proof-of-concept payload structure.

No verified exploit code is reproduced here. See the linked VulnCheck advisory for technical exploitation details.

Detection Methods for CVE-2020-37031

Indicators of Compromise

• Unexpected calc.exe or other child processes spawned by the Simple Startup Manager executable
• Crashes of Simple Startup Manager 1.17 with access violation events in the Windows Application Event Log
• Anomalous memory regions marked executable within the Simple Startup Manager process
• Presence of File input strings exceeding 268 bytes in application input files or logs

Detection Strategies

• Monitor process lineage to flag any child process created by Simple Startup Manager, since the application should not spawn executables under normal use
• Alert on Windows Error Reporting (WER) entries citing stack buffer overflow or DEP violations involving the Simple Startup Manager binary
• Inspect input artifacts for oversized File parameter values that match the 268-byte exploitation pattern

Monitoring Recommendations

• Enable command-line and process creation auditing through Windows Event ID 4688 with full command-line capture
• Track loading of unusual DLLs or memory allocations with PAGE_EXECUTE_READWRITE within the Simple Startup Manager process
• Forward endpoint telemetry to a centralized data lake for retrospective hunting on the indicators above

How to Mitigate CVE-2020-37031

Immediate Actions Required

• Remove Simple Startup Manager 1.17 from production endpoints where it is not strictly required
• Restrict execution of the application to trusted users through Windows AppLocker or Software Restriction Policies
• Block untrusted input files from being processed by the application
• Enable system-wide Address Space Layout Randomization (ASLR) and Control Flow Guard (CFG) where supported

Patch Information

No vendor patch is referenced in the available advisories. Vendor product information is available at the Ashkon Startup Manager product page. Until a fixed version is released, treat the software as end-of-life for security purposes and use the workarounds below.

Workarounds

• Uninstall Simple Startup Manager 1.17 and use an alternative startup management tool
• Run the application under a low-privilege account inside an application sandbox such as Windows Sandbox
• Enforce Windows Defender Exploit Guard with Arbitrary Code Guard (ACG) and Strict Handle Checks for the process
• Apply application allowlisting to prevent untrusted child processes from launching from the Simple Startup Manager executable

# Configuration example: enforce Exploit Protection mitigations for the binary
Set-ProcessMitigation -Name "StartupManager.exe" -Enable DEP,EmulateAtlThunks,ForceRelocateImages,BottomUp,HighEntropy,SEHOP,TerminateOnError,ACG,BlockDynamicCode