CVE-2022-3480: Denial-of-Service vulnerability in PHOENIX CONTACT mGuard product family

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-11-15 · updated 2026-06-17
Weakness: CWE-770

Description

A remote, unauthenticated attacker could cause a denial-of-service of PHOENIX CONTACT FL MGUARD and TC MGUARD devices below version 8.9.0 by sending a larger number of unauthenticated HTTPS connections originating from different source IP’s. Configuring firewall limits for incoming connections cannot prevent the issue.

Affected products

Phoenixcontact Fl Mguard Centerport Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Centerport Vpn-1000 Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Core Tx Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Core Tx Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Delta Tx/Tx Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Delta Tx/Tx Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Gt/Gt Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Gt/Gt Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Pci4000 Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Pci4000 Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Pcie4000 Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Pcie4000 Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs2000 Tx/Tx-B Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs2000 Tx/Tx Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs2005 Tx Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs4000 Tx/Tx-M Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs4000 Tx/Tx-P Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs4000 Tx/Tx Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs4000 Tx/Tx Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs4004 Tx/Dtx Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Rs4004 Tx/Dtx Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Smart2 Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Fl Mguard Smart2 Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Tc Mguard Rs2000 3G Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Tc Mguard Rs2000 4G Att Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Tc Mguard Rs2000 4G Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Tc Mguard Rs2000 4G Vzw Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Tc Mguard Rs4000 3G Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Tc Mguard Rs4000 4G Att Vpn Firmware: before 8.9.0 — fixed in 8.9.0
Phoenixcontact Tc Mguard Rs4000 4G Vpn Firmware: before 8.9.0 — fixed in 8.9.0

How to fix

Upgrade to a fixed version: Phoenixcontact Fl Mguard Centerport Firmware 8.9.0; Phoenixcontact Fl Mguard Centerport Vpn-1000 Firmware 8.9.0; Phoenixcontact Fl Mguard Core Tx Firmware 8.9.0; Phoenixcontact Fl Mguard Core Tx Vpn Firmware 8.9.0; Phoenixcontact Fl Mguard Delta Tx/Tx Firmware 8.9.0; Phoenixcontact Fl Mguard Delta Tx/Tx Vpn Firmware 8.9.0; Phoenixcontact Fl Mguard Gt/Gt Firmware 8.9.0; Phoenixcontact Fl Mguard Gt/Gt Vpn Firmware 8.9.0; Phoenixcontact Fl Mguard Pci4000 Firmware 8.9.0; Phoenixcontact Fl Mguard Pci4000 Vpn Firmware 8.9.0; Phoenixcontact Fl Mguard Pcie4000 Firmware 8.9.0; Phoenixcontact Fl Mguard Pcie4000 Vpn Firmware 8.9.0. Check the vendor advisory for mitigations.

References

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