CVE-2026-84190: LibreNMS before 26.5.0 Remote Code Execution via AboutController
LibreNMS versions before 26.5.0 contain a remote code execution vulnerability in the AboutController where the snmpget configuration parameter is passed to shellexec() without proper validation. An authenticated administrator can modify the snmpget configuration to point to a malicious executable file and trigger code execution by accessing the /about endpoint.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
LibreNMSto a version that resolves this vulnerability.Fixed in 26.5.0
Event History
Frequently Asked Questions
What access does an attacker need to exploit this issue?
The attacker must be authenticated as a LibreNMS administrator. They need permission to modify the snmpget configuration parameter.
How is code execution triggered after the configuration is changed?
The attacker points the snmpget configuration to a malicious executable file, then accesses the /about endpoint. The vulnerable controller passes the configured value to shell_exec().
Which installations should be treated as affected?
LibreNMS versions before 26.5.0 are affected. The provided information does not identify any configuration prerequisite beyond an administrator being able to modify the snmpget setting.