FastnetmonApplication · Pavel Odintsov

CVE-2026-48694

HIGH · 8.1 CVSS v3.1 Published 2026-05-26
Fix available
A fix is available. Upgrade to after 1.2.9 or later.
See remediation →
87/100
Remediation priority · High
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

FastNetMon Community Edition through 1.2.9 has a configuration injection vulnerability in the Juniper router integration plugin (src/juniper_plugin/fastnetmon_juniper.php). The $IP_ATTACK variable from argv[1] is directly interpolated into Juniper NETCONF set-configuration commands at lines 69 and 90 without any validation. An attacker can inject arbitrary Juniper CLI commands by embedding newlines followed by set/delete commands, potentially achieving full router compromise.

MitigationImplement strict input validation for the $IP_ATTACK variable to ensure it contains only valid IP address characters, and escape or use parameterized methods for NETCONF command construction to prevent command injection.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
FastnetmonApplication
Affected:<= 1.2.9

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm FastNetMon installation
    Locate FastNetMon installation directory and identify the version by checking version files, about page, or running 'fastnetmon --version' if available
    Affected if FastNetMon is installed and version is 1.2.9 or lower
  2. Verify Juniper plugin file exists
    Check if src/juniper_plugin/fastnetmon_juniper.php exists in the FastNetMon installation directory
    Affected if The Juniper plugin file exists in the installation
  3. Check if Juniper integration is configured
    Review FastNetMon configuration files (typically in /etc/fastnetmon/ or config/ directory) for juniper-related settings such as enable_juniper_plugin, juniper_host, juniper_user, or similar Juniper NETCONF parameters
    Affected if Juniper router integration is enabled in FastNetMon configuration
  4. Inspect vulnerable code in plugin
    Examine src/juniper_plugin/fastnetmon_juniper.php and look at lines around 69 and 90 where $IP_ATTACK variable is used in NETCONF command construction; check if the variable is directly interpolated into shell commands without validation or escaping
    Affected if The $IP_ATTACK variable from argv[1] is directly used in command strings without sanitization at the specified lines

A user is affected if FastNetMon Community Edition version 1.2.9 or lower is installed with the Juniper plugin enabled and the vulnerable code directly interpolates user-controlled input into NETCONF commands.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to a release after 1.2.9
Interim mitigation

Implement strict input validation for the $IP_ATTACK variable to ensure it contains only valid IP address characters, and escape or use parameterized methods for NETCONF command construction to prevent command injection.

Fix this in Fastnetmon Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing5.0 h
  • Review / QA3.0 h
17.0 hours of engineering $2,970
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-48694 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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