dbcve.org
JunosOperating system · Juniper

CVE-2022-22217

MEDIUM · 6.5 CVSS v3.1 Published 2022-07-20
Fix available
A fix is available. Upgrade to 19.1 or later.
See remediation →
70/100
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 Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an adjacent unauthenticated attacker to cause a Denial of Service (DoS). The issue is caused by malformed MLD packets looping on a multi-homed Ethernet Segment Identifier (ESI) when VXLAN is configured. These MLD packets received on a multi-homed ESI are sent to the peer, and then incorrectly forwarded out the same ESI, violating the split horizon rule. This issue only affects QFX10K Series switches, including the QFX10002, QFX10008, and QFX10016. Other products and platforms are unaffected by this vulnerability. This issue affects Juniper Networks Junos OS on QFX10K Series: All versions prior to 19.1R3-S9; 19.2 versions prior to 19.2R1-S9, 19.2R3-S5; 19.3 versions prior to 19.3R3-S6; 19.4 versions prior to 19.4R2-S7, 19.4R3-S8; 20.1 versions prior to 20.1R3-S4; 20.2 versions prior to 20.2R3-S4; 20.3 versions prior to 20.3R3-S2; 20.4 versions prior to 20.4R3-S2; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2-S1, 21.2R3; 21.3 versions prior to 21.3R2.

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

On Juniper QFX10K Series switches with VXLAN configured, malformed MLD packets received on a multi-homed Ethernet Segment Identifier (ESI) are incorrectly forwarded back out the same ESI after being sent to the peer, violating the split-horizon rule and causing a packet loop that leads to DoS.

MitigationUpgrade Junos OS on affected QFX10K Series switches to a fixed version listed in the Juniper advisory; if immediate upgrade is not possible, consider disabling VXLAN on multi-homed ESI configurations as a temporary mitigation.

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
JunosOperating system
Affected:< 19.1= 19.1= 19.2= 19.3= 19.4= 20.1= 20.2= 20.3= 20.4= 21.1= 21.2= 21.3

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
None
Availability
High

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

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 device model
    Run 'show chassis hardware' or 'show version' to confirm the device is a QFX10K Series switch
    Affected if Device model is NOT QFX10K Series (other Juniper switches are not affected by this specific vulnerability)
  2. Check Junos version
    Run 'show version' to obtain the installed Junos OS version
    Affected if Version matches any of these affected versions: 19.1, 19.2, 19.3, 19.4, 20.1, 20.2, 20.3, 20.4, 21.1, 21.2, or 21.3, or is earlier than 19.1
  3. Verify VXLAN is configured
    Run 'show configuration protocols vxlan' or 'show configuration protocols evpn' to check for VXLAN-related configuration
    Affected if VXLAN is NOT configured (the vulnerability only affects switches with active VXLAN configuration)
  4. Confirm multi-homed ESI configuration
    Run 'show configuration protocols evpn esi' or 'show configuration protocols evpn multi-homing' to identify Ethernet Segment Identifier (ESI) multihoming setup
    Affected if No multi-homed ESI is configured (the flaw specifically requires an ESI on a multi-homed Ethernet segment)

A user is affected only if they are running an affected Junos version on a QFX10K Series switch with both VXLAN and a multi-homed ESI configuration actively in use.

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 19.1 or later
Fixed in 19.1
Interim mitigation

Upgrade Junos OS on affected QFX10K Series switches to a fixed version listed in the Juniper advisory; if immediate upgrade is not possible, consider disabling VXLAN on multi-homed ESI configurations as a temporary mitigation.

Recommended fix High confidence

19.1R3-S9, 19.2R3-S5, 19.3R3-S6, 19.4R3-S8, 20.1R3-S4, 20.2R3-S4, 20.3R3-S2, 20.4R3-S2, 21.1R3, 21.2R3, or 21.3R2 (depending on your version branch)

  1. 1. Identify the current Junos OS version running on the QFX10K Series switch (QFX10002, QFX10008, or QFX10016) using 'show version' command
  2. 2. Identify which version branch you are currently on (19.1, 19.2, 19.3, etc.) from the output
  3. 3. Based on your current version branch, upgrade to the corresponding fixed version: For 19.1.x upgrade to 19.1R3-S9 or later; For 19.2.x upgrade to 19.2R3-S5 or later (or 19.2R1-S9); For 19.3.x upgrade to 19.3R3-S6 or later; For 19.4.x upgrade to 19.4R3-S8 or later; For 20.1.x upgrade to 20.1R3-S4 or later; For 20.2.x upgrade to 20.2R3-S4 or later; For 20.3.x upgrade to 20.3R3-S2 or later; For 20
  4. 4. Download the appropriate Junos OS software package from the Juniper Networks support portal (kb.juniper.net)
  5. 5. Upload the software package to the switch using 'file copy' or USB transfer
  6. 6. Install the upgrade using 'request system software add <package-name>' command
  7. 7. Reboot the device using 'request system reboot' command to complete the installation
  8. 8. After reboot, verify the new version is installed using 'show version' and confirm the vulnerability is resolved
Caveat Standard Junos upgrade precautions apply: backup configuration, test in lab environment first, plan maintenance window as upgrade may cause brief disruption

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

Fix this in Junos Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing8.0 h
  • Review / QA4.0 h
18.0 hours of engineering $3,080
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,928.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2022-22217 — 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-2022-22217 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