CVE-2019-25597: Nsasoft Nsauditor DOS Vulnerability

CVE-2019-25597 Overview

CVE-2019-25597 is a buffer overflow vulnerability affecting NSauditor version 3.1.2.0, a network security auditing tool developed by NSASoft. The vulnerability exists in the SNMP Auditor component's Community field, where improper input validation allows local attackers to crash the application by supplying an excessively long string. When an attacker pastes a large payload into the Community field and triggers the Walk function, it causes a denial of service condition, rendering the application unusable.

Critical Impact

Local attackers can exploit this buffer overflow vulnerability to crash NSauditor, disrupting network security auditing operations and potentially affecting organizational security monitoring capabilities.

Affected Products

• NSASoft NSauditor 3.1.2.0

Discovery Timeline

• 2026-03-22 - CVE-2019-25597 published to NVD
• 2026-03-24 - Last updated in NVD database

Technical Details for CVE-2019-25597

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-Bounds Write), a type of memory corruption issue where the application writes data past the boundaries of an allocated buffer. The flaw resides specifically in the SNMP Auditor module's handling of user input in the Community field.

The buffer overflow occurs because NSauditor fails to properly validate the length of input data before copying it into a fixed-size memory buffer. When an attacker provides input that exceeds the expected buffer size, the excess data overwrites adjacent memory locations, corrupting application state and ultimately causing the program to crash.

This is a local attack vector, meaning an attacker must have access to the system where NSauditor is installed to exploit the vulnerability. The attack requires no special privileges and no user interaction beyond the attacker's own actions. While the vulnerability does not directly lead to code execution based on the available data, it results in complete loss of application availability.

Root Cause

The root cause of this vulnerability is improper input validation in the SNMP Auditor Community field. The application allocates a fixed-size buffer to store the community string but does not enforce proper boundary checks when processing user-supplied input. This allows oversized input to overflow the buffer and corrupt memory, leading to application instability and crashes.

Attack Vector

The attack is carried out locally through the following method:

1. An attacker with local access to a system running NSauditor 3.1.2.0 opens the SNMP Auditor module
2. The attacker crafts an excessively long string payload designed to exceed the buffer allocation
3. The attacker pastes this payload into the Community field within the SNMP Auditor interface
4. Upon triggering the Walk function, the oversized input is processed without proper length validation
5. The buffer overflow occurs, corrupting memory and causing NSauditor to crash

Additional technical details regarding the exploitation methodology can be found in the Exploit-DB #46757 entry and the VulnCheck Advisory.

Detection Methods for CVE-2019-25597

Indicators of Compromise

• Unexpected NSauditor application crashes, particularly when using SNMP Auditor functionality
• Windows Event Log entries indicating application faults in nsauditor.exe
• Presence of crash dump files associated with NSauditor processes
• Abnormally large text inputs found in application logs or memory dumps

Detection Strategies

• Monitor for repeated NSauditor process crashes using Windows Event Log correlation
• Implement endpoint detection rules to identify buffer overflow patterns targeting NSauditor
• Configure application crash monitoring for nsauditor.exe on critical security workstations
• Deploy SentinelOne Singularity to detect and alert on memory corruption attempts

Monitoring Recommendations

• Enable detailed logging for security tool workstations where NSauditor is deployed
• Configure alerts for multiple NSauditor process terminations within a short timeframe
• Monitor user activity logs for unusual clipboard operations or file access patterns before crashes
• Review endpoint telemetry for signs of intentional denial of service activity against security tools

How to Mitigate CVE-2019-25597

Immediate Actions Required

• Restrict access to systems running NSauditor to trusted personnel only
• Implement application whitelisting to prevent unauthorized users from interacting with NSauditor
• Consider deploying NSauditor in an isolated environment with limited network exposure
• Monitor for updated versions from NSASoft that may address this vulnerability
• Review and limit local user privileges on systems with security auditing tools installed

Patch Information

At the time of NVD publication, no official patch information was provided by NSASoft. Organizations should monitor the NSASoft website for security updates and newer versions that may address this vulnerability. Contact NSASoft support directly for guidance on available fixes or mitigation options.

Workarounds

• Restrict local access to workstations running NSauditor to only authorized security personnel
• Implement input validation at the application layer if customization options are available
• Consider alternative SNMP auditing tools while awaiting an official patch from NSASoft
• Deploy application isolation technologies to contain potential crashes and prevent broader system impact
• Regularly backup NSauditor configurations to minimize recovery time after potential crashes