dbcve.org
Junos Os EvolvedOperating system · Juniper

CVE-2023-44190

MEDIUM · 5.4 CVSS v3.1 Published 2023-10-11
Fix available
A fix is available. Upgrade to 21.4 or later.
See remediation →
59/100
Remediation priority · Elevated
No privileges 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
An Origin Validation vulnerability in MAC address validation of Juniper Networks Junos OS Evolved on PTX10001, PTX10004, PTX10008, and PTX10016 devices allows a network-adjacent attacker to bypass MAC address checking, allowing MAC addresses not intended to reach the adjacent LAN to be forwarded to the downstream network. Due to this issue, the router will start forwarding traffic if a valid route is present in forwarding-table, causing a loop and congestion in the downstream layer-2 domain connected to the device. This issue affects Juniper Networks Junos OS Evolved on PTX10001, PTX10004, PTX10008, and PTX10016: * All versions prior to 21.4R3-S5-EVO; * 22.1 versions prior to 22.1R3-S4-EVO; * 22.2 versions 22.2R1-EVO and later; * 22.3 versions prior to 22.3R2-S2-EVO, 22.3R3-S1-EVO; * 22.4 versions prior to 22.4R2-S1-EVO, 22.4R3-EVO; * 23.2 versions prior to 23.2R1-S1-EVO, 23.2R2-EVO.

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

An Origin Validation vulnerability in MAC address validation in Juniper Networks Junos OS Evolved on PTX10001, PTX10004, PTX10008, and PTX10016 devices allows a network-adjacent attacker to bypass MAC address checking. This causes the router to forward traffic with MAC addresses not intended for the adjacent LAN if a valid route exists in the forwarding table, creating loops and congestion in downstream Layer-2 domains.

MitigationUpgrade Junos OS Evolved to the fixed versions (21.4R3-S5-EVO, 22.1R3-S4-EVO, 22.2R1-S2-EVO or later, 22.3R2-S2-EVO/22.3R3-S1-EVO, 22.4R2-S1-EVO/22.4R3-EVO, 23.2R1-S1-EVO/23.2R2-EVO or later). If immediate patching is not possible, implement strict MAC filtering at layer-2 domain boundaries to prevent unauthorized MAC addresses from being forwarded.

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
Junos Os EvolvedOperating system
Affected:< 21.4= 21.4= 22.1= 22.2= 22.3= 22.4= 23.2

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
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
Low

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

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. Identify the device model
    Run 'show chassis hardware' or 'show system information' to confirm the hardware model
    Affected if The device is a PTX10001, PTX10004, PTX10008, or PTX10016
  2. Check the Junos OS Evolved version
    Run 'show version' and note the Junos OS Evolved version number
    Affected if The installed version is < 21.4, 21.4, 22.1, 22.2, 22.3, 22.4, or 23.2 (compare against the exact version string shown)
  3. Verify Layer-2 forwarding is configured
    Run 'show configuration | match "layer2"' or check for bridge domain/VLAN configurations with 'show bridge domain'
    Affected if Layer-2 bridging or VLAN features are active on the device
  4. Check for active forwarding entries
    Run 'show route forwarding-table' to view the forwarding table entries
    Affected if There are active routes in the forwarding table that could be exploited for MAC address hijacking

You are affected if you are running Junos OS Evolved on a PTX10001/04/08/16 device with an affected version AND have Layer-2 forwarding enabled with active routes in the forwarding table.

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.

dbcve · scoped
Upgrade available Upgrade to 21.4 or later
Fixed in 21.4
Interim mitigation

Upgrade Junos OS Evolved to the fixed versions (21.4R3-S5-EVO, 22.1R3-S4-EVO, 22.2R1-S2-EVO or later, 22.3R2-S2-EVO/22.3R3-S1-EVO, 22.4R2-S1-EVO/22.4R3-EVO, 23.2R1-S1-EVO/23.2R2-EVO or later). If immediate patching is not possible, implement strict MAC filtering at layer-2 domain boundaries to prevent unauthorized MAC addresses from being forwarded.

Recommended fix High confidence

Upgrade to 21.4R3-S5-EVO (or later 21.4.x), 22.1R3-S4-EVO (or later 22.1.x), 22.3R3-S1-EVO (or later 22.3.x), 22.4R3-EVO (or later 22.4.x), or 23.2R2-EVO (or later 23.2.x) - select the appropriate branch based on your current version

  1. 1. Identify the current Junos OS Evolved version running on the PTX device (PTX10001, PTX10004, PTX10008, or PTX10016) using 'show version'
  2. 2. Download the appropriate fixed Junos OS Evolved image from the Juniper Networks support portal (supportportal.juniper.net) - select the version appropriate for your hardware platform
  3. 3. Upload the Junos OS Evolved software image to the device using 'request system software add <path-to-package>' or via the web management interface
  4. 4. Reboot the device to apply the new software version using 'request system reboot'
  5. 5. After reboot, verify the new version is running with 'show version' and confirm the fix is applied
  6. 6. Verify that MAC address validation is functioning correctly and the device no longer forwards unexpected MAC addresses
Caveat Standard Junos upgrade precautions apply - review release notes for any configuration changes, and plan for appropriate maintenance window as reboot is required

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Junos Os Evolved Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing8.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,800
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,080.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-44190 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2023-44190 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data