CVE-2025-34078
A local privilege escalation vulnerability exists in NSClient++ 0.5.2.35 when both the web interface and ExternalScripts features are enabled.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.61%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A local privilege escalation vulnerability exists in NSClient++ 0.5.2.35 when both the web interface and ExternalScripts features are enabled. The configuration file (nsclient.ini) stores the administrative password in plaintext and is readable by local users. By extracting this password, an attacker can authenticate to the NSClient++ web interface (typically accessible on port 8443) and abuse the ExternalScripts plugin to inject and execute arbitrary commands as SYSTEM by registering a custom script, saving the configuration, and triggering it via the API. This behavior is documented but insecure, as the plaintext credential exposure undermines access isolation between local users and administrative functions.
- CVSS 4.0
- 7.3 HIGHCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.61% probability · 47th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-522
- Affected
- nsclient/nsclient\+\+
- Source
- disclosure@vulncheck.com
References
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/windows/local/nscp_pe.rbExploit, Third Party Advisory
- https://vulncheck.com/advisories/nsclient-localtoremote-system-compromiseExploit, Third Party Advisory
- https://www.exploit-db.com/exploits/46802Exploit, Third Party Advisory, VDB Entry
- https://www.exploit-db.com/exploits/48360Exploit, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.