Nssm224 Privilege Escalation Updated - [new]

For instance, if nssm.exe installs a service with the path: C:\Program Files\App Folder\nssm.exe Windows may try to interpret this sequentially: C:\Program.exe (with args Files\App Folder\nssm.exe ) C:\Program Files\App.exe (with args Folder\nssm.exe ) C:\Program Files\App Folder\nssm.exe 2. The Exploitation Mechanism

The attacker places a malicious executable named App.exe inside C:\Program Files\App Folder\ . nssm224 privilege escalation updated

Validate that the folder containing the NSSM binary and the hosted application restricts write access to administrative accounts only. Standard users should only possess Read and Execute permissions. For instance, if nssm

If NSSM is used to run a service, do run the service as LocalSystem unless absolutely required. Instead, create a dedicated, low‑privileged service account with only the minimum permissions needed for the application to function. This containment reduces the impact of any successful replacement attack — the malicious payload will run with only the service account’s limited privileges, not full SYSTEM access. Standard users should only possess Read and Execute

The technical root cause is straightforward but dangerous: nssm.exe is installed with permissions that allow to overwrite or replace the file. This is often a result of third‑party installers copying NSSM into directories that inherit overly permissive Access Control Lists (ACLs) from their parent folder.

This guide provides an updated overview of the vulnerabilities, exploitation techniques, and critical remediation steps for NSSM 2.24. 1. What is NSSM and Why is it Vulnerable?