Arbitrary Command Injection Affecting fastnetmon package, versions <1.1.4-1ubuntu0.1~esm1


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
0.23% (14th percentile)

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  • Snyk IDSNYK-UBUNTU2004-FASTNETMON-16913750
  • published12 Jun 2026
  • disclosed26 May 2026

Introduced: 26 May 2026

NewCVE-2026-48694  (opens in a new tab)
CWE-77  (opens in a new tab)

How to fix?

Upgrade Ubuntu:20.04 fastnetmon to version 1.1.4-1ubuntu0.1~esm1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream fastnetmon package and not the fastnetmon package as distributed by Ubuntu. See How to fix? for Ubuntu:20.04 relevant fixed versions and status.

FastNetMon Community Edition through 1.2.9 contains a configuration injection vulnerability in the Juniper router integration plugin. In src/juniper_plugin/fastnetmon_juniper.php, the $IP_ATTACK variable (received from argv[1]) is directly interpolated into Juniper NETCONF set-configuration commands at lines 69 and 90 without any validation or sanitization. Line 69: $conn->load_set_configuration("set routing-options static route {$IP_ATTACK} community 65535:666 discard"). Line 90: $conn->load_set_configuration("delete routing-options static route {$IP_ATTACK}/32"). An attacker who can control the IP address string can inject additional Juniper CLI configuration commands by embedding newline characters followed by arbitrary set/delete commands. This could modify the router's routing table, firewall filters, user accounts, or any other configuration element accessible via NETCONF. The impact is full router compromise.

CVSS Base Scores

version 3.1