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High VDE-2019-020 1 CVE

PHOENIX CONTACT: improper access control exists on FL NAT devices when using MAC-based port security

Published Oct 29, 2019 · Updated May 22, 2025 · Revision 3

Summary

If MAC-based port security or 802.1x port security is enabled, the FL NAT 2xxx will unintentionally grant access to unauthorized devices in case of routed transmission.
'''
Subnet 2---(Ports belonging to subnet 2)
|
FL NAT 2xxx
|
(Ports belonging to subnet 1, port sec ON)---- 2nd device
|
-- unauthorized device

'''
The unauthorized device can access other devices in subnet 2 but cannot access the 2nd device in subnet 1.

Details

Impact
If port security is enabled on a port, a device not authorized by MAC based port security or 802.1x based port security can access another subnet via the FL NAT 2xxx device that is routing between the subnet the unauthorized device is residing in and the 2nd subnet.

Mitigation
User should take care that network security is not relying solely on separating subnets with MAC or 802.1x based port security if the FL NAT 2xxx device is serving as a router between the subnets.

Remediation
This vulnerability will be fixed with the next firmware release V2.90, which will be available Q02/2020.

Vulnerabilities 1

  • Unscored —

    Improper access control exists on PHOENIX CONTACT FL NAT 2208 devices before V2.90 and FL NAT 2304-2GC-2SFP devices bef…

Revision history

  1. #3

    Fix: version space, added distribution, quotation mark

  2. #2

    Fix: correct certvde domain, added alias, added self-reference

  3. #1

    Initial revision.

References