Description
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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | fastnetmon | 1.2.9-1 | — |
| Debian 13 | fastnetmon | 1.2.9-0+deb13u1 | — |
| Debian 12 | fastnetmon | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | fastnetmon | No fix yet | — |
| Ubuntu 25.10 | fastnetmon | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | fastnetmon | 1.2.8+git20250911-2ubuntu0.1~esm1 | USN-8429-1 |
| Ubuntu Pro 24.04 LTS | fastnetmon | 1.2.6-1ubuntu0.1~esm1 | USN-8429-1 |
| Ubuntu Pro 20.04 LTS | fastnetmon | 1.1.4-1ubuntu0.1~esm1 | USN-8429-1 |
Advisories 1
- USN-8429-1 fastnetmon vulnerabilities Ubuntu Security Notices (USN) · Jun 16, 2026