CVE-2018-20434 LibreNMS arbitrary OS commands execution

Critical 9.8 Published 24 Apr 2019 Updated 5 Aug 2024

Remote attackers can execute arbitrary OS commands in LibreNMS by injecting malicious input during device creation and triggering a specific capture request.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2018-20434?

CVE-2018-20434 is a critical command injection vulnerability in Librenms Librenms, published on 24 Apr 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

LibreNMS 1.46 allows remote attackers to execute arbitrary OS commands by using the $_POST['community'] parameter to html/pages/addhost.inc.php during creation of a new device, and then making a /ajax_output.php?id=capture&format=text&type=snmpwalk&hostname=localhost request that triggers html/includes/output/capture.inc.php command mishandling.

Weakness: CWE-78

Which versions are affected by CVE-2018-20434?

2 open source packages ship an affected version, including librenms/librenms. It affects 1 product.

Package	Affected	Fixed in
`librenms/librenms` Packagist	All versions	None
`librenms/librenms` Packagist	All versions	None

Products include Librenms Librenms.

How do I fix CVE-2018-20434?

No fix has been published for CVE-2018-20434 yet. Limit exposure of the affected software until one is available.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2018-20434 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2018-20434 exists.

Public exploit code: 1 Metasploit module, 2 Exploit-DB entries and 1 proofs of concept on GitHub.

All Librenms Librenms vulnerabilities

Sources

Also known as GHSA-62q7-qj6g-gvr7.