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Meraki Mx64 FirmwareOperating system · Cisco

CVE-2022-20933

HIGH · 8.6 CVSS v3.1 Published 2022-10-26
Fix available
A fix is available. Upgrade to 16.16.6 / 17.10.1 or later.
See remediation →
95/100
Remediation priority · Urgent
Remotely reachable 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
A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z3 Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of client-supplied parameters while establishing an SSL VPN session. An attacker could exploit this vulnerability by crafting a malicious request and sending it to the affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to crash and restart, resulting in the failure of the established SSL VPN connections and forcing remote users to initiate a new VPN connection and re-authenticate. A sustained attack could prevent new SSL VPN connections from being established. Note: When the attack traffic stops, the Cisco AnyConnect VPN server recovers gracefully without requiring manual intervention. Cisco Meraki has released software updates that address this vulnerability.

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

A denial of service vulnerability exists in the Cisco AnyConnect VPN server component of Cisco Meraki MX and Z3 Teleworker Gateway devices. The vulnerability stems from insufficient validation of client-supplied parameters during SSL VPN session establishment. An unauthenticated remote attacker can send specially crafted malicious requests to cause the VPN server to crash and restart, resulting in failed VPN connections and preventing new connections until the attack ceases.

MitigationApply the Cisco Meraki software updates that have been released to address this vulnerability. Schedule appropriate maintenance windows to apply updates while minimizing impact on remote workers.

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
Meraki Mx64 FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1
Meraki Mx64w FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1
Meraki Mx65 FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1
Meraki Mx65w FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1
Meraki Mx67 FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1
Meraki Mx67cw FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1
Meraki Mx67w FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1
Meraki Mx68 FirmwareOperating system
Affected:>= 16.2.0, < 16.16.6>= 17.0.0, < 17.10.1

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
None
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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 the device model
    Access the Meraki dashboard or check the physical device label to confirm the model number is MX64, MX64w, MX65, MX65w, MX67, MX67cw, MX67w, or MX68
    Affected if The device is any of these eight models
  2. Locate the firmware version
    In the Meraki dashboard, go to Network-wide > Monitor > Appliance status, or use the API call GET /devices/{serial}/firmware
    Affected if The firmware version falls within >= 16.2.0 and < 16.16.6, OR >= 17.0.0 and < 17.10.1
  3. Verify SSL VPN is configured
    In the Meraki dashboard, navigate to Security & SD-WAN > AnyConnect VPN (or SSL VPN settings). Check if AnyConnect VPN is enabled and clients are configured
    Affected if AnyConnect VPN or SSL VPN feature is enabled on the device
  4. Confirm VPN connectivity issues
    Observe VPN connection logs or test new VPN connections. The vulnerability causes the VPN server to crash and restart repeatedly during exploitation
    Affected if VPN connections are failing or the VPN server is repeatedly restarting

The device is affected if it is an MX64/65/67 series model running firmware between 16.2.0 and 16.16.5, or between 17.0.0 and 17.10.0, and has AnyConnect VPN enabled.

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 16.16.6 / 17.10.1 or later
Fixed in 16.16.617.10.1
Interim mitigation

Apply the Cisco Meraki software updates that have been released to address this vulnerability. Schedule appropriate maintenance windows to apply updates while minimizing impact on remote workers.

Recommended fix High confidence

16.16.6 or later, or 17.10.1 or later

  1. Identify the current firmware version of the affected Meraki MX or Z3 device via the Meraki dashboard (Network > Devices > Select device > Status)
  2. Log in to the Meraki dashboard and navigate to Network-wide > Firmware
  3. Under Firmware upgrades, select 'Use static firmware'
  4. Choose a fixed firmware version: 16.16.6 or later, OR 17.10.1 or later
  5. Apply the firmware upgrade to the affected devices and verify successful completion
  6. After upgrade, confirm the AnyConnect VPN server is operational and monitor for stability

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

Fix this in Meraki Mx64 Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.

Scan for this in your stack

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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-2022-20933 in production — separate from our analysis above.

No notes yet

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